Details will be added as they become available.
Agenda subject to change.
★ Denotes that the lead author is a student
Updated 5 October 2018
7:00 am – 8:30 am
Continental Breakfast / Exhibits Open / Poster Viewing
7:30 am – 8:30 am
8:30 am – 10:00 am
Concurrent Session D
- Regional Paleolimnology Reveals Widespread Anthropogenic Impacts
Regional Paleolimnology Reveals Widespread Anthropogenic Impacts
Euan D. Reavie1, Mark B. Edlund2, Katya E. Kovalenko1, and Joy M. Ramstack Hobbs2
1Natural Resources Research Institute, University of Minnesota Duluth, Duluth, Minnesota; 2St. Croix Watershed Research Station, Science Museum of Minnesota, Marine on St. Croix, Minnesota
Long-term records of environmental condition are critical for diagnosing region-wide anthropogenic impacts and establishing best management practices. Extending paleolimnology from single lakes to large regions should enable detection of widespread stressors such as climate change and atmospheric deposition. Using assemblage similarity analysis on diatom paleorecords from more than 100 Minnesota lakes we characterized periods of spatially consistent assemblage changes over the last 150 years. While we expected localized stressors such as agriculture and urban development to drive assemblage reorganization in specific lakes, overarching stressors such as climate change should be discernable in the regional analysis. We hypothesized that this overarching shift would manifest as diatom assemblage reorganization from low-nutrient to higher-nutrient taxa and, more recently, species that indicate warmer atmospheric temperatures, warmer surface waters, and shifts in lake thermal structure. We specifically test whether diatom communities are stronger indicators of multiple regional stressors than other common paleolimnological proxies.
- Applying Paleolimnological Techniques to Reservoirs: Challenges and Possibilities
Applying Paleolimnological Techniques to Reservoirs: Challenges and Possibilities
Victoria L.S. Chraïbi
Tarleton State University, Stephenville, Texas
Paleolimnology provides useful long-term data sets and holistic perspectives of lakes that inform management. These analyses have been applied to reservoirs with mixed results. Riverine impoundments do not follow hydrological or sedimentation models similar to most natural lakes, creating obstacles for the application of paleolimnology. For example, fast sedimentation rates, dredging, and the young age of reservoirs pose issues for dating sediment and ensuring undisturbed core chronologies. However, it is worth developing modified techniques that account for the unique properties of reservoirs. There is the potential to synchronize paleolimnological studies with modern limnological monitoring in reservoirs in order to understand how reservoir-specific processes are reflected in longer-term records. Paleolimnological analysis of reservoirs is especially promising for arid regions such as Texas and the American southwest, where natural lakes do not exist from which to procure sediment cores. This will enable the application of paleolimnology to better inform long-term management for a suite of problems that face riverine impoundments, including changes in hydrology and biotic structure due to decreasing precipitation, changing seasonality, and human activities like impoundment, diversion, and irrigation.
- Paleolimnological Assessment of Lakes on the Kissimmee Chain, South Florida USA
Paleolimnological Assessment of Lakes on the Kissimmee Chain, South Florida, USA
Thomas J. Whitmore1, Melanie A. Riedinger-Whitmore1, Francesca M. Lauterman1, Neil Rose2, Handong Yang2, Jason H. Curtis3, Christine Leonard1, Daniel Franklin1, Zachary Leyton Rivera-Reed1, Deveny E. Evans1, and Karla Alvarado1
1University of South Florida St. Petersburg, St. Petersburg, Florida; 2Environmental Change Research Centre, University College London, London, United Kingdom; 3Department of Geological Sciences, University of Florida, Gainesville, Florida
The Kissimmee Chain of Lakes in south Florida consists of twenty lakes that flow southward through the Kissimmee River to Lake Okeechobee and the Florida Everglades. The lakes originally were associated with wetlands and had high-colored DOC, but reference conditions are poorly documented. Agriculture and urban development in the 20th century led to the loss of associated wetlands, and significant nutrient loading caused degradation of water quality. High nutrient conditions exert downstream effects on Lake Okeechobee and have implications for restoration of the Everglades. We present a paleolimnological study that determined reference water-quality conditions for lakes on the Kissimmee Chain. We maintain that associated wetlands and native macrophyte communities exerted important influences on lake processes, so understanding their presence during the past is essential for more holistic assessment of ecosystem change and for effective management. We collected 10 sediment cores from Lakes Tohopekaliga, East Lake Tohopekaliga, Kissimmee, and Cypress and examined sedimented diatoms, algal and cynaobacterial pigments, stable isotopes of organic matter, pollen, and sedimented macrofossils. Diatom-based statistical models indicate that pre-disturbance limnetic total P values were in the range of 40–45 µg/L. Chronologies and nutrient accumulation rates were calculated using 210Pb and 137Cs radionuclides. Diatoms showed progressive changes from benthic to planktonic communities during eutrophication, but with onset of cyanobacteria, planktonic forms were competitively displaced, and diatoms that depend on wind-generated resuspension became dominant. We also examine evidence of changes in wetland influences and macrophyte communities as indicated by pollen and plant macrofossils.
- Innovative Approaches in Paleolimnology: How Recent Advances Can Inform Lake Management
Innovative Approaches in Paleolimnology: How Recent Advances Can Inform Lake Management
Melanie Riedinger-Whitmore, Thomas Whitmore, Daniel Franklin, Francesca Lauterman, and Deborah L. Howard
Department of Biological Sciences, University of South Florida St. Petersburg, St. Petersburg, Florida
The protection and management of lakes require an understanding of how water quality and watershed conditions have changed through time. Paleolimnology is the standard approach used to define pre-disturbance and reference conditions, and in developing restoration goals and best management practices. Common paleolimnological methods employed in lake management studies include analyses of biological fossils and sediment geochemistry. Recent analytical advances in UV-Vis Near-infrared spectroscopy (NIRS) and in molecular techniques supplement these classic approaches and provide the opportunity to use the paleolimnological record to explore a new suite of questions that can address contemporary lake-management issues. NIRS uses multivariate statistics to analyze absorption spectra (400–2500 nm) and to determine the physical and chemical properties of sediment samples. Regional calibration data sets have been developed to assess algal productivity, nutrients, organic compounds, and contaminants in surface sediment and core samples. NIRS is a rapid, non-destructive technique that permits sample absorption spectra to be archived for use in future studies. In applied metagenomic studies, environmental DNA is extracted and sequenced from sediments using molecular techniques and can be used to document aquatic organisms that do not leave recognizable fossils. Sedimentary DNA has been used to examine population and community-level questions related to algae, zooplankton, bacteria, and fungi. This approach also has been used to examine historical changes in aquatic biodiversity. We present examples of how we are using these approaches in our paleolimnological research in Florida, and we discuss how they are applicable to lake management.
- Nutrient Management Challenges in Coeur d’Alene Lake, Idaho
Nutrient Management Challenges in Coeur d’Alene Lake, Idaho
Idaho Department of Environmental Quality, Coeur d’Alene, Idaho
Coeur d’Alene Lake is a primarily oligotrophic lake that is a critical economic and cultural resource for northern Idaho. The lake also holds over 75 million tons of metal contaminated sediments that result from historic mining practices and is part of the Bunker Hill Superfund action. The metal contaminants are managed in place via a lake management plan that seeks to sustain high levels of hypolimnetic oxygen in order to trap metals within the sediments and facilitate long term remediation and restoration. Oxygen levels in the lake are managed by limiting productivity via a nutrient management strategy. These actions also support managing overall lake water quality for beneficial use. Harmful algae blooms occur in nearby lakes and are also a potential challenge for Coeur d’Alene Lake. Trend analyses indicate that, except for lead, dissolved metals levels are declining in the lake. In contrast, trophic status is trending towards a more productive system. These factors increase the risk of metals remobilization from the sediments and pose a long-term nutrient and oxygen management challenge. Phosphorus loads are increasing in many of the Coeur d’Alene Basin’s watersheds and are primarily non-point source. Potential drivers of these changes will be discussed within the context of the known and unknown factors, as well as nutrient management activities.
- Managing Large Inland Lakes: The Need for an Integrated Management Approach for Successful Lake Management
Managing Large Inland Lakes: The Need for an Integrated Management Approach for Successful Lake Management
Jennifer L. Jermalowicz-Jones
Restorative Lake Sciences, Spring Lake, Michigan
Although an integrated lake management approach could be applied to most lakes, it is especially important for the successful management of large (> 1,000 acre) inland lakes. This evaluation focuses on Houghton Lake which is a 22,044-acre natural, glacial lake located in northern Michigan. The lake has two sizeable bays and several major tributaries and an outlet to the Muskegon River at the north region of the lake. In addition, the lake has over thirty canals that are developed. The lake has approximately 30.5 miles of shoreline and a mean depth of approximately 8.5 feet, so it is vulnerable to aquatic invasive species and water quality degradation.
Each component of the lake (i.e., bays, tributaries, flats, canals) is being managed with different methods and technologies since the problems associated with each area are unique and vary at the spatial level. Such methods include replanting of native wild rice in the north bay of the lake, reduction of invasive hybrid watermilfoil and starry stonewort throughout the entire lake, application of laminar flow aeration and bioaugmentation to certain impaired canals, and implementation of nutrient and solid filters to tributaries that were associated with increased pollutant loads. Specialized planning for each improvement type was needed in order to assure the Houghton Lake Improvement Board and the Houghton Lake community that the myriad issues facing the lake could individually be addressed and ultimately lead to substantial gains in the overall ecological balance of the lake.
- Results of Innovative Restoration Techniques at Lake Apopka, Florida
Results of Innovative Restoration Techniques at Lake Apopka, Florida
St. Johns River Water Management District, Palatka, Florida
Lake Apopka is a shallow, 30,800-acre eutrophic lake in central Florida. The lake’s health is challenged by three threats; eutrophication due to excessive phosphorus (P) loading, wildlife effects of residual organochlorine pesticides (OCPs) and severe multi-year droughts which significantly impact water levels, water quality and critical habitats. To address these threats, the St. Johns River Water Management District (District) is implementing a multi-part restoration program which utilizes a variety of innovative techniques to address each threat. To remove excess bioavailable P from the lake’s water, the District is operating a 760-acre recirculating filter marsh which annually filters approximately 40% of the lake’s volume. From 2003 to 2017, 119 million pounds of suspended solids and 71,355 pounds of P were removed. In addition, a rough fish harvest program removed 26.5 million pounds of fish (217,500 pounds of bioavailable P) between 1994 to 2016. Wildlife exposure to OCPs was reduced by implementing a novel soil inversion technique which buried the contaminated top foot of soil under four feet of cleaner underlying soil. This inversion technique was applied over 4,000 acres, and reduced remediation costs by > 95% when compared to traditional soil remediation techniques. To address water availability, the District is planning two projects: one to increase flood protection by temporarily storing water for subsequent lake level augmentation and second, a large solar panel farm which in addition to reducing electricity costs, will increase water yield by reducing evapotranspiration losses from a project area and reduce water used to generate steam at powerplant.
- Pacification: The New Narrative on Lake Management
Pacification: The New Narrative on Lake Management
Lake Advocates, Duluth, Minnesota
The theme for this conference, “Innovations in Lake Management,” suggests we are on track to address lake management challenges. Yet, nearly 50 years after the Clean Water Act, the quality of the nation’s lakes, on average, has not changed. And new threats are emerging – invasive species, climate change, HABs, intensified agriculture and increasing population. Our narrative emphasizes all that is being done to protect, manage and restore our lakes – diverting our attention from the realities. Trends are going the wrong way and positive outcomes are lacking overall. Here, I examine narrative and realities of the management of Minnesota lakes. I find that 18-times more phosphorus-impaired lakes have been added than removed from the impaired waters list annually, there are 1,200 mercury-impaired lakes (none have been removed), chlorides are impacting urban lakes and there are no plans to remedy this, aquatic invasive species infestations continue despite increased awareness and inspections, and the prevalence and intensity of harmful algae blooms is increasing. All this despite the investment of 100s of millions of dollars annually. Our narratives emphasize partnerships, watersheds, busy hands and an overall can-do attitude with the effect of de-sensitizing or distracting from the elephants in the room – water quality impacts of agriculture, lack of measurable progress in lake quality, climate change, invasive species and road salt use. What can be done and what is the role of lake managers?
- Use of Remote Sensing Techniques to Monitor Harmful Algal Blooms
Use of Remote Sensing Techniques to Monitor Harmful Algal Blooms
Christian Corbeil and Julie Camy
Groupe Hémisphères, Québec, Québec, Canada
Under the increasing effects of climate change, the phenomenon of harmful blue-green algae (or cyanobacteria) algal blooms continues to intensify in lakes across North America. Indeed, the ability of some species of cyanobacteria to produce toxins is a significant problem for public health and for recreational use.
The SCHORE (System for CHlOrophyll Remote Estimation) application has been developed to become one of the most innovative computer tools in terms of monitoring the water quality of lakes. Traditional cyanobacteria monitoring methods are based on visual observations and punctual sampling performed following the observation of excessive proliferation of cyanobacteria in lakes and streams. SCHORE allows for the remote estimation of the concentration of a green pigment present in water, chlorophyll a, which is used as an indicator of the presence, spatial distribution and concentration of cyanobacteria in freshwater lakes.
SCHORE is available in two versions, which produces daily or weekly maps of the spatial distribution of chlorophyll a. The application relies on high-resolution imagery (LANDSAT and SENTINEL), which allows it to be used on lakes larger than 2 ha. The Chl-a estimation maps are then integrated into a technical sheet which presents environmental and meteorological data available at the time of the analysis.
This presentation aims to present a complementary decision-making tool for lake quality monitoring or the implementation of preventive actions to be taken at the watershed level. A concrete application will be presented concerning the protection of a drinking water source.
- Cyanobacteria from Space: Satellite Imagery for Bloom Monitoring
★ Igor Ogashawara
Cyanobacteria from Space: Satellite Imagery for Bloom Monitoring
Igor Ogashawara and Lin Li
Department of Earth Sciences, Indiana University-Purdue University at Indianapolis, Indianapolis, Indiana
Cyanobacterial blooms (CBs) have been a concern especially for inland waters. Traditional monitoring methods usually are not suitable for monitoring CBs on large spatial and temporal scales, but remote sensing has been used to fill this gap. Remote monitoring of CBs relies on the optical properties of pigments. While few orbital sensors can measure it, the Ocean and Land Color Instrument (OLCI) on-board the Sentinel-3 satellite has the adequate spectral resolution. The goal of this study is to evaluate OLCI’s potential to identify CBs. To do this, OLCI images were collected over the Western part of Lake Erie (USA) for the summer of 2016 and 2017. An analysis of single spectral bands and band ratios was used to explore the use of satellite imagery for the estimation of PC. Using the combination of both datasets, none of the single bands shown to be correlated with PC concentrations (R2 < 0.1). For the band ratio analysis, the highest R2 was 0.26 for the ratio between bands centered at 709 nm and 673 nm. This low performance is attributed to low concentrations of the pigment (average concentration 3.49 mg/m3). When using only concentrations higher than 10 mg/m3, the highest R2 was 0.87 for the ratio between 412 and 709 nm. These results show that OLCI can be used to identify CBs. However, more work is needed for the estimation of low pigment concentrations. By solving these issues, remote sensing can be used to support water quality management.
- Remote Sensing of Harmful Algal Blooms and Water Quality Characteristics in Kentucky Lakes
Remote Sensing of Harmful Algal Blooms and Water Quality Characteristics in Kentucky Lakes
Kentucky Division of Water, Frankfort, Kentucky
Lakes are a valuable economic and environmental resource for the Commonwealth of Kentucky. The Kentucky Division of Water (KDOW) currently monitors 108 of approximately 200 lakes greater than 25 acres in size that are located within the Commonwealth. These lakes are currently monitored following a five-year rotation among designated basin management units. Due to resource limitations, KDOW is investigating the use of free Landsat 8 and Sentinel 2 satellite imagery in order to estimate water quality in unsampled lakes and assist in harmful algal bloom monitoring. Remote sensing has been successfully used in other states to predict Secchi disk transparency. In 2017, Watershed Watch of Kentucky and KDOW partnered to initiate a pilot program for citizen volunteers to assist with lake monitoring. A primary goal of this volunteer monitoring program is to be able to assist with the detection of harmful algal blooms within the Commonwealth. From June through October of 2017, 10 volunteers collected a total of 42 Secchi disk transparency measurements from 10 locations on Herrington Lake, correlating sample dates with Landsat 8 overpass. KDOW used this data along with atmospherically corrected satellite imagery via Landsat 8 to predict Secchi disk transparency for the lake. A stepwise regression was used to determine an appropriate equation which accurately predicts Secchi disk transparency for Herrington Lake. In 2018, the study will continue with the possibility of including chlorophyll a measurements for Herrington Lake and additional sites for Secchi disk measurements.
- Sustainably Solving Legacy Phosphorus and Nitrogen in Landscapes with Wetlands and Wetlaculture
Sustainably Solving Legacy Phosphorus and Nitrogen in Landscapes with Wetlands and Wetlaculture
William J. Mitsch
Everglades Wetland Research Park, Florida Gulf Coast University, Naples, Florida; School of Geosciences, University of South Florida, Tampa, Florida; The Ohio State University. Columbus, Ohio
The world is faced with unprecedented threats to our aquatic ecosystems from excessive nutrients caused especially by agricultural and urban runoff. More than 750 aquatic ecosystems suffer from degraded ecosystem services with impairments described as hypoxia, dead zones, and harmful algal blooms, most due to pollution caused by excessive nitrogen and phosphorus. At the same time, it has also been estimated that, on a global scale, we have lost half of our original wetlands to our current extent of 8 to 12 million km2, with most of that loss in the 20th century. We are proposing here a sizeable increase in the wetland resources around the world to solve the diminishing wetland problem but with the strategic purpose of mitigating the excess phosphorus and nitrogen in a sustainable fashion. Examples include minimizing phosphorus inflows to the Florida Everglades with treatment wetlands and reducing nutrient inflows to Lake Erie in the Laurentian Great Lakes by restoring parts of the Great Black Swamp, formerly a 400,000 ha wetland west of Lake Erie. The status of our wetlaculture physical models (mesocosms) in Ohio and Florida for solving nutrient saturation of our landscapes and aquatic ecosystems and recycling (flipping) those nutrients back to agriculture—defined as wetlaculture—will be described. Our mesocosm experiments in south Florida (analog of the Florida Everglades) and in NW Ohio (analog of a restored Great Black Swamp) will be presented.
- Nutrient Retention by Wetland Mesocosms in the First Year of a Wetlaculture Hydrologic Experiment at Buckeye Lake Ohio
★ Bingbing Jiang
Nutrient Retention by Wetland Mesocosms in the First Year of a Wetlaculture Hydrologic Experiment at Buckeye Lake, Ohio
Bingbing Jiang1,2 and William J. Mitsch2,1
1School of Geosciences, University of South Florida, Tampa, Florida; 2Everglades Wetland Research Park, Florida Gulf Coast University, Naples, Florida
Nutrient overloads have caused problems in aquatic ecosystems around the world for decades. As nutrient retention by wetlands is complicated, understanding of wetland functions is needed to avoid failed management of restored wetlands or inappropriate design of created wetlands. A 28-mesocosm wetlaculture (wetland + agriculture) compound using 1 m2 mesocosms was constructed in 2016 and planted in October 2016 with the sedge Schoenoplectus tabernaemontani. Initial soils showed P concentrations of 519 ± 12 (9) µg/mL and N concentrations of 0.20 ± 0.01 (9) %. Bi-weekly water quality sampling began in April 2017 of soluble reactive phosphorus (SRP), total phosphorus (TP), nitrate+nitrite (NO3+NO2-N), total Kjeldahl nitrogen (TKN), and total nitrogen (TN) in mesocosm inflows and outflows. The mesocosms were randomly assigned to a 7 × 2 × 2 hydrologic experiment involving 2 water depth and 2 hydraulic loading rates (HLR). Early data in 2017 suggest the mesocosms are already sinks of phosphorus and nitrogen, probably because they were constructed in an area that has not been farmed recently. The mesocosms were nutrient sinks, with a removal rate of TP (26 ± 6% (n = 111) and TN 36 ± 3% (n = 224)). Comparing the different hydrological conditions, shallow-water level mesocosms showed higher removal rates of TP (44 ± 8%, n = 55), than did deep-water level mesocosms (9 ± 10%, n = 56)). The potential applications and limitations of applying these results to full-sale wetlaculture demonstration projects will be discussed. This wetlaculture study could eventually demonstrate the potential of nutrient retention by wetlands with subsequent recycling back to agriculture/horticulture in the Buckeye Lake region.
- Constructed Wetlands and Nutrient Removal in Grand Lake St. Marys Watershed
Constructed Wetlands and Nutrient Removal in Grand Lake St. Marys Watershed
Stephen J. Jacquemin1, Phillip Poore1, Gestawn McDonald1, Jocelyn Birt1, and Theresa Dirksen2
1Wright State University – Lake Campus, Celina, Ohio; 2Mercer County Community and Economic Development, Celina, Ohio
Constructed wetlands can be an important management tool to reduce nutrient rich agricultural runoff. The objective of this study was to assess removal efficiency of two constructed wetlands on tributaries of Grand Lake St. Marys (Prairie Creek and Coldwater Creek). Both wetlands are approximately 30+ acres, situated in glacial till Blount soils typical of northwest Ohio, and consist of a series of increasingly shallow pools planted using a mix of emergent wetland vegetation (e.g., grasses, sedges, rushes, forbs, shrubs). The wetlands draw stream water at a set rate using a variable pump (between 1 and 3 million gallons per day) and exhibit residence times of 1 to 3 days depending on flow and volume. For this study, water samples were collected weekly 2017–2018 (n = 46) from inflow and outflow points where they were analyzed for nutrient (nitrate-N, total phosphorus, dissolved reactive phosphorus) concentrations following EPA colorimetric methods. Overall, while both wetlands experienced high mean nutrient inputs (concentrations in mg/L) ranging from below detectable limits to 19.1 NO3–, 2.5 TP, and 1.1 DRP, high removal efficiencies (often > 75%) produced significantly reduced outflow concentrations (paired t tests; p < 0.05) largely consistent with EPA recommended TMDL target values for watersheds of this size (~20 mi2: 1.0 mg/L NO3, 0.10 mg/L TP). Mean monthly stream discharge rates compared with wetland discharge data (continuously monitored using pressure transducers) revealed that both wetlands processed between 10% and 100% of monthly flows, depending on the season. This study demonstrates the importance of constructed wetlands towards watershed restoration.
- Understanding the Role of Wetland Ecoservices in Protecting Water Quality from Potential Zoonotic Pathogen Spread: Arcobacter Transmission Dynamics in Western Lake Erie Wetland and Adjacent Swimming Beach
Understanding the Role of Wetland Ecoservices in Protecting Water Quality from Potential Zoonotic Pathogen Spread: Arcobacter Transmission Dynamics in western Lake Erie wetland and Adjacent Swimming Beach
Chris Rea1, David Hsu2, Cheonghoon Lee1, Chenlin Hu1, and #Jiyoung Lee1,3
1College of Public Health, Division of Environmental Health Sciences, The Ohio State University, Columbus, Ohio; 2Environmental Science Graduate Program, The Ohio State University, Columbus, Ohio; 3Department of Food Science & Technology, The Ohio State University, Columbus, Ohio
Arcobacter spp. presence and spatiotemporal variability was studied in Canada Geese (Branta canadensis) and waters of a wildlife dense wetland and adjacent swimming beach of southwestern Lake Erie, Ohio, USA from May 2012 to April 2013. Molecular techniques, including qPCR targeting 23s rDNA, were used to detect, identify, and quantify Arcobacter spp. in water and fecal samples. A human microbial source-tracking marker (HF183) was also used. Arcobacter presence was identified at each of the water-sampling sites during the year and in 75.8% (n = 72) of all the water samples but was not found in Canada Geese fecal samples nor was human fecal contamination detected. The mean Arcobacter gene copy number/mL for all sites was 3.1 × 103. Phylogenetic analysis indicated Arcobacter sequences were closely related to A. butzleri, the most prevalent and hazardous species to human and animal health. Arcobacter concentrations and prevalence were highest at sites where water enters the wetland and levels were reduced by the wetland. Likely Arcobacter contamination sources were determined to be avian species; however, agricultural run-off may also contribute. This study demonstrates Arcobacter presence in a large freshwater lake where the predominant influence on water quality is agriculture and wildlife. Establishing Arcobacter presence throughout Lake Erie, and the Great Lakes more generally, is important when considering human and animal exposure risks. Conserving healthy near shore wetlands is important to support safe surface water and may aid in the control and prevention of human and animal illness.
- Whole Lake Combined PAC-Phoslock Treatment to Manage Eutrophication and Cyanobacteria
★ Maíra Mucci
Whole-Lake Combined PAC-Phoslock Treatment to Manage Eutrophication and Cyanobacteria
Maíra Mucci1, Guido Waajen2, and Miquel Lürling1
1Aquatic Ecology & Water Quality Management Group, Wageningen University, Wageningen, The Netherlands; 2Water Authority Brabantse Delta, Breda, The Netherlands
Lake de Kuil (The Netherlands, 6.7 ha, maximum depth 9 m) suffered from cyanobacterial blooms since the early 1990s as a consequence of eutrophication. To control internal loading and cyanobacteria the lake was treated with a low dose of flocculent (4 tons of iron chloride) and a solid phase phosphate sorbent (42 tons of Phoslock®) in May 2009. The treatment aimed to target both dissolved and particulate phosphate, and to block P-release from the sediment. The treatment was successful reducing total phosphate, chlorophyll a and increasing water quality. Ongoing diffuse P-inputs, however, have gradually moved the lake back towards a eutrophic state. Thus, a re-application of flocculent and Phoslock® and flocculent (polyaluminium chloride, PAC) was done in May 2017. We have been monitoring the lake before, during, and after the application. Water samples over depth were taken to analyse nutrients, chlorophyll a, turbidity, cyanotoxins and pH. In situ, Secchi depth and oxygen concentration were measured. Internal loading was monitored before and after the treatment. On May 8, 10.5 tons of Phoslock® were applied to the lake (30 mg/L-1) as ballast to sink the algae. The day after, 6000 L of Polyaluminium chloride were applied (2.1 mg Al L-1) to flocculate the cells, while on May 10, 22.05 tons of Phoslock® were injected in the hypolimnion layer (at 5.5 meters) to target the internal loading. The results of the monitoring will be presented shedding light on the efficacy and durability of the treatment.
- Evaluation of a Whole Lake Eutrophication Management Technique Using Combined Flocculation and In situ Phosphorus Immobilization
★ Frank van Oosterhout
Evaluation of a Whole-Lake Eutrophication Management Technique Using Combined Flocculation and In situ Phosphorus Immobilization
Frank van Oosterhout, Maira Mucci, and Miquel Lurling
Wageningen University, Wageningen, Gelderland, The Netherlands
Cyanobacterial blooms led to swimming bans in Lake Rauwbraken (The Netherlands). System analysis revealed that this lake was eutrophicated by external phosphorus (P) loads (1.51 mg P m-2 day-1) which over 40 years led to 15.1 mg P m-2 day-1 internal load from legacy P in the sediment. Thus, to manage eutrophication and mitigate cyanobacterial blooms the lake was treated by combining a low dose of flocculent (polyaluminium chloride) with a solid phase phosphate fixative (Phoslock®) in April 2008. Based on two years pre- and ten years post-treatment monitoring, the annual means of Secchi depth increased from 3.5 to 4.2 m and hypolimnetic oxygen concentration from 0.86 to 5.02 mg l-1; turbidity decreased from 5.5 to 2.0 NTU, chlorophyll a concentrations from 16.5 to 5.4 µg l-1, the percentage of cyanobacteria from 64% to 15%, total P from 154 to 18 µg l-1 and total nitrogen from 0.96 to 0.36 mg l-1. The release of filterable reactive phosphate from the sediment reduced from 15.1 mg P m-2 day-1 pre-treatment to 1.7 mg m-2 day-1 post-treatment in 2008, 2.3 mg m-2 day-1 in 2011 and 4.7 mg P m-2 day-1 in 2013. The treatment successfully improved water quality and no swimming bans occurred till then. However, post-treatment significant trends downwards in Secchi depth and the increased in P-release from the sediment indicate that after 10 years of intervention the lake is returning to a eutrophic state as a result of the ongoing external P-loads.
- Control of Floating Algal Mats in a Highly Frequented Recreational Lake
Control of Floating Algal Mats in a Highly Frequented Recreational Lake
Karin Finsterle1, Tim S. Epe2, Said Yasseri2, and Karin Pall3
1Phoslock Europe GmbH, Zug, Switzerland; 2Institut Dr. Nowak GmbH & Co. KG, Ottersberg, Germany; 3Systema Bio- & Management Consulting GmbH, Vienna, Austria
Benthic, mat-forming cyanobacteria in freshwater systems are an increasing phenomenon in many parts of the world. Apart from being a risk for human health when they rise to the surface, the mats also present aesthetic problems, limit recreational activities and thus can adversely affect local economies. We present results from a pilot project conducted on a small, highly frequented recreational lake in Austria, where the occurrence of floating algal mats negatively affected the ecosystem service provided by the lake. A comprehensive systems analysis of the water body revealed a dynamic chain of physical, chemical and biological interactions between the catchment, water column and sediment which trigger the formation of benthic, mat forming algal conglomerates. On the basis of our system analysis, a two-step management strategy was developed to achieve the dual targets of ecological recovery and ecosystem service preservation. In the first phase, a targeted application of lanthanum modified bentonite (LMB, Phoslock) reduced the available phosphorus fraction in the sediment and established the desired pre-conditions necessary for the growth of macrophytes. The second phase consisted of systematic and accurate planting of selected Charophyte species, typical for this environment. The results demonstrate that the adopted management concept is a promising technique to tackle the proliferation of benthic algal mats.
- Phoslock® Research in the Netherlands
Phoslock® Research in The Netherlands
Miquel Lürling1, Frank van Oosterhout1, Maíra Mucci1, and Guido Waajen2
1Wageningen University, Wageningen, The Netherlands; 2Water Authority Brabantse Delta, Breda, The Netherlands
During the heat wave year 2006, many lakes and ponds in The Netherlands were suffering from massive cyanobacteria blooms. Legacy phosphorus (P) in lake beds and diffuse loading are viewed as the main sources fuelling those blooms, because point sources have been tackled adequately in The Netherlands; full compliance with the EU Urban Waste Water Treatment Directive and many WWTP have an additional third treatment step to remove phosphate and nitrogen. To improve water quality and mitigate cyanobacterial nuisance, research was directed to in-lake measures effectively targeting legacy P and diffuse groundwater P load. Phoslock® was identified as promising tool and since summer 2006 Phoslock® research started, first in the laboratory which was up scaled to enclosure experiments and to large scaled compartment experiments. In two urban ponds, 300 m2 and 400 m2 compartments were created that received different treatments: dredging, fish stock manipulation and Phoslock® addition. The treatments tackling internal loading (dredging and Phoslock® addition) improved water quality noticeably. Water clarity improved to bottom sight, chlorophyll a was reduced below 10 µg/l and submerged macrophytes reached almost complete cover. The control and fish stock manipulated compartments remained turbid, chlorophyll a concentrations reached as high as 100–300 µg/l and submerged macrophytes were virtually absent. Sediment P-release was reduced in the Phoslock® treated compartments and lanthanum was clearly elevated in the first 5 cm sediment after two years. Evidently, chemical P-fixation using Phoslock® is cheaper than sediment removal in urban ponds and as effective in bringing water quality to a more acceptable state.
10:00 am – 10:30 am
Refreshment Break / Exhibits Open / Poster Viewing
10:30 am – 12:00 pm
Concurrent Session E
- Multi-Indicator, Ecologically Based Paleolimnological Studies Help Optimize Lake-Management and Restoration Strategies
Multi-Indicator, Ecologically Based Paleolimnological Studies Help Optimize Lake-Management and Restoration Strategies
Thomas Whitmore1, Carl D. Sayer2, Helen Bennion2, and Thomas A. Davidson3
1Department of Biological Sciences, University of South Florida St. Petersburg, St. Petersburg, Florida; 2Environmental Change Research Centre, Department of Geography, University College London, London, United Kingdom; 3Department of Bioscience and Arctic Research Centre (ARC), Aarhus University, Silkeborg, Denmark
In the last four decades, paleolimnological studies have served an important role in assessing human impacts on lakes for which pre-disturbance water-quality data are scarce or nonexistent. Statistical modeling has provided quantitative estimates of change in pH from acid precipitation, change in limnetic nutrient concentrations, and change in climate. With respect to eutrophication, lake management has focused greatly on past limnetic nutrient inferences because nutrients lend themselves to mitigation. Lake managers and freshwater ecologists, however, have become aware that reducing nutrient loads does not adequately restore systems because eutrophication is multifactorial and involves complex changes in food webs and lake processes. Applied paleolimnological studies help optimize management strategies based on site-specific conditions and drivers. This presentation examines ecologically based paleolimnological approaches that involve multiple biological indicators, particularly keystone groups such as aquatic plants. Studies that examine long-term changes in indicator groups such as diatoms, zooplankton, macrophytes, algae, cyanobacteria, and pollen evidence of associated wetlands are capable of providing more comprehensive description of system change and its causes. Changes in lake systems are often perceived as catastrophic and sudden, but careful paleolimnological studies have demonstrated that change is often a progressive succession that occurred over a time scale of many decades. A more complete understanding of long-term system change enables us to better identify Early Warning Indicators that can be used to more effectively monitor and protect lake systems, and to avoid changes that are irreversible or costly to mitigate.
- The Long-Term Effects of Multiple Environmental Stressors on Shifting Benthic Production in a Large Shallow Lake
★ Michael Murphy
The Long-Term Effects of Multiple Environmental Stressors on Shifting Benthic Production in a Large Shallow Lake
Michael Murphy1 and Jesse C. Vermaire1,2
1Department of Geography and Environmental Studies, Carleton University, Ottawa, Ontario, Canada; 2Institute of Environmental Science, Carleton University, Ottawa, Ontario, Canada
White Lake is a large, shallow (mean depth 3.1 m) lake located in Eastern Ontario, Canada, and an important recreation and tourism site in the region. Similar to many lakes in the area White Lake is experiencing multiple environmental stressors including nutrient enrichment, climate warming, and the recent colonization by the invasive zebra mussels (Dreissena polymorpha). Lake users and property owners are increasingly concerned about water quality changes in the lake and management plans for the lake require an understanding of how these multiple environmental stressors are interacting to impact water quality. Unfortunately monitoring data for White Lake only begins in 2014 and therefore no information exists on pre-impact conditions in the lake and how these environmental stressors have interacted to alter water quality in the system. To assess long-term water quality changes in White Lake in response to these multiple environmental stressors, two sets of replicate sediment cores have been obtained from the lake, dated using 210Pb, and sectioned at 0.5 cm intervals for organic content and diatom analysis. Diatom analysis suggest that the lake was becoming increasingly eutrophic since ~1980, however the recent invasion by zebra mussels has reversed this trend with diatoms suggesting nutrient limitation in the open water environment. Recent monitoring data indicates that the zebra mussel invasion has increased the percent of the lake bottom with sufficient light for photosynthesis from 20% to 90% of the lake area. These data suggest that White Lake is becoming an increasingly benthic system and that colonial benthic algae and/or macrophyte cover will expand within the lake. This research provides insight into how zebra mussels impact primary producers in shallow lakes that are sensitive to shifts in nutrients and turbidity.
- Development of the Mill Pond Remediation Plan
Development of the Mill Pond Remediation Plan
Stephen J. Souza, Christopher Mikolajczyk, and Jesse Smith
Princeton Hydro, LLC, Ringoes, New Jersey
Mill Pond, located in Water Mill, Suffolk County, New York is a 92-acre freshwater lake. It is categorized by NYSDEC as eutrophic and has at times been impacted by cyanobacteria (blue-green algae) blooms. The measures taken over the years by the Mill Pond Association (MPA) and the Town of Southampton (TOS) to address the occurrence of cyanobacteria blooms have included the installation of a solar-powered aeration system and the application of the nutrient sequester Phoslock. Reportedly, neither the aeration system nor the PhosLock treatment yielded any long-term positive water quality benefits. Given the pond’s eutrophic status, continued problems with cyanobacteria blooms, and the less than desired benefits attained through past restoration efforts, the TOS and the MPA engaged Princeton Hydro to conduct a detailed, comprehensive lake and watershed study and use the resulting data to prepare a “remediation plan” for Mill Pond.
This presentation discusses the in-lake and watershed data developed in support of the Mill Pond remediation plan, details the study’s findings and discusses the proposed elements of the plan. Details are provided of Mill Pond’s hydrologic budget, external nutrient loading, the relative importance of legacy agricultural loading and the impacts related to bioturbation attributable to an invasive carp population. The presentation shows how the combination of measured and modeled data were used in the development of the plan and the key strategies recommended to lessen the occurrence and severity of cyanobacteria blooms.
- A Model-Based Approach for Developing Lake Management Plans
A Model-Based Approach for Developing Lake Management Plans
Seyoum Yami Gebremariam, Paul McCormick, and Paul Rochelle
Metropolitan Water District of Southern California, La Verne, California
The development of lake management plans requires a solid understanding of past as well as present hydrologic and water quality conditions. Reconstructing historical conditions for most lakes is hampered by limited data availability and an absence of information on many key environmental parameters. Hydrodynamic and water-quality modeling tools can address this problem by allowing key time-series data sets to be generated with relatively modest data input requirements. We used the CE-QUAL-W2 model to reconstruct 15 years of lake-wide hydrologic and water quality history for Diamond Valley Lake, a large drinking-water-supply reservoir in southern California. Available input data was limited to: 1) daily flow and lake stage data; 2) monthly water-quality data at a single station; and 3) available meteorological data from nearby weather stations. The model was successfully calibrated to simulate numerous hydrologic and water-quality parameters over the period of record and allowed for the identification of critical tipping points in time when the lake experienced changes in trophic state (e.g., nutrient levels and sediment nutrient release, phytoplankton growth rates, hypolimnetic anoxia) from the baseline condition. The model was used to develop a lake management plan based on this historical information and an assessment of various management scenarios for improving future water quality.
- Implementation and Results of a Comprehensive Urban Shallow Lake Monitoring Plan to Understand Ecosystem Dynamics and Inform Holistic Lake Management
Implementation and Results of a Comprehensive Urban Shallow Lake Monitoring Plan to Understand Ecosystem Dynamics and Inform Holistic Lake Management
Sarah Wein, Britta Suppes, and Bob Fossum
Capitol Region Watershed District, Saint Paul, Minnesota
Como Lake is a 70.5-acre urban shallow lake located within Capitol Region Watershed District (CRWD) in St. Paul, Minnesota. Shallow depth, coupled with large nutrient inputs from runoff, have had significant negative impacts to the lake’s overall health. Como Lake experiences frequent summer algal blooms and has been listed as impaired for nutrients, chloride, and mercury. Water chemistry and physical parameters have been collected since 1984, but additional monitoring was needed to better understand in-lake water quality drivers and ecosystem dynamics. In response, CRWD implemented a comprehensive monitoring plan in 2014. This enhanced monitoring plan increased: data collection of the biological community (aquatic macrophytes, fish populations, phytoplankton, and zooplankton); the frequency of physical/chemical data collection, including winter monitoring; and the collection of continuous hypolimnetic dissolved oxygen at multiple locations. Sediment cores were also extracted to measure phosphorus release rates. Analysis showed that Como Lake has a low-diversity plant community and an overabundance of curly-leaf pondweed, an imbalanced fishery consisting mainly of planktivorous fish, and a phytoplankton community dominated by blue-green algae. Data also revealed that hypolimnetic phosphorus significantly increased recently and that the lake has extended periods of anoxia. Results indicate that internal loading is the primary source of phosphorus to the lake. Managing key drivers of internal loading (anoxia, plant senescence, fishery imbalance) will be critical for restoring balance to the lake. This additional data will guide the development of the 2018 Como Lake Management Plan which will define adaptive management strategies for meeting long-term water quality goals.
- Too Many Innovations? Recent History on a Multi-Dimensional Small Lake Restoration – Mountain Lake, San Francisco
Too Many Innovations? Recent History on a Multi-Dimensional Small Lake Restoration – Mountain Lake, San Francisco
University of California, Berkeley California
Mountain Lake, one of only three natural lakes in San Francisco, recently was restored using an innovative mixture of extensive dredging and bottom and shore reshaping, watershed wetlands construction, biomanipulation (replacement of all higher trophic levels, exotic tree removal from riparian zones, planting leafy submerged aquatic plants), and two aeration methods. In the first year, TP, ammonia, and sediment anoxia dropped; chlorophyll and nitrate less so but Secchi depth doubled, and this urban lake became almost mesotrophic. The next year was California’s wettest and followed a 4-year drought. As expected, nitrate rose six-fold but, surprisingly, TP did not (TP not correlated to salinity, but nitrate was). A huge blue-green algae bloom arose in lake spring and was traced to two causes: the high spring nitrate &/or an unusual fault in the aeration system. Once the aeration was corrected by mid-summer, internal loading of nutrients and blue-green scums declined but not sufficiently to restore the past years higher water quality. Several lessons learned include 1) aeration pipe joints can leak silently, 2) there is a month’s lag between aeration on and effects on sediment nutrient releases but no lag for getting oxygen into deep water for the biota, 3) in urban settings, control of watersheds nitrate requires more active wetlands or nitrate trenches while TP control may only need storm water wetlands or other good BMPs, 4) the results or too many innovations at once are tricky to interpret!
- Building a Smart Lake Erie: Intelligent Water Management as a Regional Economic Driver
Building a Smart Lake Erie: Intelligent Water Management as a Regional Economic Driver
Max Herzog1, Bryan Stubbs1, Chris Winslow2, John Bratton3, Ken Loparo4, Dorothy Baunach5, Laura Johnson6, George Bullerjahn7, and Sudhir Kshirsagar8
1Cleveland Water Alliance, Cleveland, Ohio; 2Ohio Sea Grant, Columbus, Ohio; 3LimnoTech, Ann Arbor, Michigan; 4Case Western Reserve University, Cleveland, Ohio; 5DigitalC, Cleveland, Ohio; 6Heidelberg University, Tiffin, Ohio; 7Bowling Green State University, Bowling Green, Ohio; 8Global Quality Corp., Cincinnati, Ohio
In February of 2017, Cleveland Water Alliance (CWA) and DigitalC teamed up to create Erie Hack, a competition that challenged Lake Erie communities to Innovate the Lake. CWA and DigitalC worked with regional partners to activate the economic potential of Lake Erie, providing continuous support and $100,000 in prizes to over 200 entrepreneurs in the US and Canada as they tackled Lake Erie’s key challenges with next-generation solutions.
Many Erie Hackers focused on harmful algal blooms, the annual ecological disaster that threatens an economic impact of $1.3 billion over the next 30 years, by envisioning an Internet of Water: a network of nanosensors and unmanned vehicles, built on underwater telemetry and intelligent analytics. As the competition came to a close, tech, utility, and community leaders came to understand the significance of this vision.
The coalition defined a forward-thinking vision for a Smart Lake Erie. They see that the urgency around algae offers a unique opportunity to deliver unparalleled value to our region’s economy and ecology. We need an intelligent monitoring system to help our utilities keep people safe and allow Ohio, Michigan, and Ontario to benchmark and optimize their efforts to reduce nutrient pollution. But, such a system also has the potential to integrate and interpret a broad range of data parameters that could impact a host of legacy and emerging challenges. Our coalition understands that a Smart Lake Erie would serve as a platform for the transformation of data into actionable strategies that leverage water resources into a regional development engine.
- Web Interoperability Services with GIS for Global Environmental Monitoring Data Management and Sharing
Web Interoperability Services with GIS for Global Environmental Monitoring Data Management and Sharing
Frank Schlaeger1 and #Jens Proche2
1KISTERS AG, Aachen, Germany; 2KISTERS North America, Roseville, California
The United Nations Global Environmental Monitoring System (GEMS) Water Program is dedicated to providing environmental water quality data (sample results and continuously measured data) of the highest quality, integrity, accessibility and interoperability. This data is provided to the public via the GEMStat website to be used in water assessments and capacity building initiatives. The water quality data currently includes more than 3,000 stations, over 100 parameters, almost four million sample records and is submitted to GEMStat by national focal points of governmental agencies.
In March 2014 the hosting of the GEMStat component was taken over by the German Federal Institute of Hydrology (FIH). The FIH completely redesigned the data storage and management component as well as the representation of data, including the data download portal.
The data storage, management and analysis system will be replaced by a custom off the shelf software with a water quality module. This module was specifically designed to manage, validate and analyse discrete sampling data along with continuously measured real time sensor data. As the water quality module is fully integrated into the system it takes advantage of features such as flexible data structuring, powerful calculations, scripting and graphing functionalities.
The new Web Interoperability Solution will provide environmental monitoring data to the public and allow specialists to easily download the data as required. The solution is a single framework for multiple web service types and serves several data sources at one time such as HTTP GET/POST KVP services (SOS1&2) and SOAP (WaterOneFlow, SOS2). The web service supports user authentication and authorization for members to view and download their data but restricts guest users from accessing directly to ensure data security. In addition to powerful web services, the solution provides time series data for specific web widgets such as creating dynamic time series graphs or displaying descriptive station metadata. The GEMS portal will be set up by applying this functionality and overlaying with GIS mapping capabilities.
The project for redesigning the new GEMStat portal started in September 2015.
- Open-Source Spectrometry for Collective Monitoring of Nutrients
Open-Source Spectrometry for Collective Monitoring of Nutrients
Jiansheng Feng, Kelly Siman, Banafsheh Khakipoor, Adam Smith, and Hunter King
University of Akron, Akron, Ohio
We present a cellphone-camera-based spectrometer for measuring phosphorus and nitrogen concentrations in water. The combined hardware/software system is designed to meet the following goals: 1) easy to make with standard makerspace equipment and requires only low-cost, readily available materials, such that it can be affordable/accessible in many schools, makerspaces, or fablabs; 2) be simple and user friendly, such as to function as a teaching tool in K–12 water-related lesson plans and in public parks; 3) produces accurate results comparable to commercial colorimeters or spectrometers; 4) allows simple aggregation of resulting data, which is shared with the users. The intent is to provide a much-needed supplementary data set for nutrient loading from local sources along the watershed, by local inhabitants, while promoting a tangible appreciation of water-related issues in young people.
- Telling the Story of Your Lake with Online Maps
Telling the Story of Your Lake with Online Maps
University of New Hampshire, Durham, New Hampshire
The scientific, volunteer and lake management communities have historically put a great deal of time and money into collecting and analyzing data about lake characteristics. In spite of these vast efforts, a relatively small amount of time has been dedicated to finding compelling ways to present this information to the wide range stakeholders involved with and affected by lake issues. While standard graphs and tables in PDF reports and PowerPoint presentations may communicate information effectively to select group, a far wider audience would be more responsive to stories, images, videos and maps that they can interact with on their own terms.
Online mapping offers the promise of a location-based, engaging method for sharing both data and multimedia in ways not possible a few short years ago. Several types of approaches to online mapping (e.g., Esri Story Maps) have dramatically expanded the ability of people to present information in a compelling online format for free (or nearly so) without any need for coding knowledge. In addition to being able to share information, these tools can also allow people to contribute data and ideas to lake groups, potentially adding new methods for engaging stakeholders and the public. This presentation will cover ways in which online mapping can be used by scientists, volunteer groups and lake managers to share data and stories about their lakes.
- The Business of Wetlaculture – Seeking Viable Business Models for Landscape-Scale Nutrient Capture
The Business of Wetlaculture – Seeking Viable Business Models for Landscape-Scale Nutrient Capture
Sam Miller1 and William J. Mitsch2
1Mendoza College of Business, University of Notre Dame, Notre Dame, Indiana; 2Everglades Wetland Research Park, Florida Gulf Coast University, Naples, Florida
Nutrient runoff is a growing challenge and as the planet’s farmers seek to feed a hungry world, the challenge is likely to intensify. The wetlaculture concept seeks to utilize wetlands in field rotation to capture and recycle nutrients at scale – an alternative that is currently being scientifically tested. Opportunities and obstacles with regard to development of business models that can create a share economic incentive to drive adoption of landscape-scale nutrient capture to address nutrient runoff issues in the Great Lakes, Florida Everglades, and elsewhere will be presented here. The wetlaculture concept includes savings farmers can realize via a reduced need to apply expensive nutrients, public sector incentives to remove acreage from active production (e.g., CRP), and other public programs such as conservation easements, wetland reserve program, water quality trading, and carbon sequestration credit programs as economic incentives. Two primary challenges exist in the economic viability of landscape scale wetland systems for nutrient capture. First is the issue of timing. Agribusiness seeks to accelerate crop cycles and output and wetland systems process nutrients more slowly than this sector requires. Mesocosm experiments can quantify x years the site needs to be a wetland for y years as a productive agriculture or horticulture field. Secondly, many of the downstream costs and impacts are externalized – i.e., not included in the economic value chain of the agricultural production system. Effected stakeholders such as tourism and municipal water quality managers face increasing costs of mitigating algal blooms that result from upstream nutrient runoff.
- Feasibility of Bundling Conservation Credits for Water Quality Trading in the Blanchard Watershed of Lake Erie
Feasibility of Bundling Conservation Credits for Water Quality Trading in the Blanchard Watershed of Lake Erie
Yanting Guo1 and Richard Moore2
1University of Findlay, Findlay, Ohio; 2The Ohio State University, Columbus, Ohio
Bundling conservation credits or “credit stacking” is a concept used in selling ecosystem credits where two or more spatially overlapping conservation practices are paid for their separate environmental service. The use of bundling credits has been pioneered in the water quality trading arena. Stacking has the potential to create incentives for landowners to increase ecological value and economic benefit with multiple kinds of credits at the same time in the same location with a reduction of paperwork on the farmer’s end. Stacking allows credit providers to lower the risk of selling only one type of credit. For example, major weather events might lower the ecological functioning of a particular conservation measure making it fail to produce one type of credit, while it still might produce other types of credits. Stacking may also be useful for financing the best conservation practice when that practice is ecologically sound but cost prohibitive. A drop-off/pick-up survey of 96 farmers in the Blanchard Watershed located in the Maumee Basin of Lake Erie was conducted in 2016 to 2017 with the goal of finding out if farmers preferred bundling conservation credits as an “All-in-One” bundle such as phosphorus, nitrogen, carbon, stream temperature, or biodiversity together rather than as separate commodities. The survey found that 70.8% of the respondents preferred the All-in-One model, 16.7% preferred the more commonly seen phosphorus trading, and 12.5% preferred trading nitrogen or temperature or biodiversity credits alone.
- Phoslock® as a Maintenance Measure to Control Cyanobacteria in a Large Brazilian Urban Lake Subjected to High Organic Load
Tiago Finkler Ferreira
The Use of Phoslock® as a Maintenance Measure to Control Cyanobacteria in a Large Brazilian Urban Lake Subjected to High Organic Load
Tiago Finkler Ferreira¹, Rafael Schmitt¹, Said Yasseri², Patrick van Goethem³, and Nigel Traill³
¹Hidroscience Consultoria e Restauração Ambiental, Porto Alegre, Brazil; ²Institut Dr. Nowak GmbH & Co., Ottersberg, Germany; ³Phoslock Europe GmbH, Zug, Switzerland
Lake Pampulha is an urban lake located in Belo Horizonte state, Minas Gerais, Brazil which has undergone intense eutrophication since the 1970s due to the constant input of organic loads from the main tributaries. The aim of this project was to restore the water quality of the Lake and control cyanobacteria using the lanthanum-modified bentonite clay (Phoslock®). A total dose of approximately 1000 tons of the product was applied to reduce internal phosphorus load from the sediment and external input from the catchment over 2016 and 2017. The total dose was divided into monthly applications due to the financial chronogram imposed by the contractor, the Municipality of Belo Horizonte. The treatment resulted in a significant reduction (> 94%) in total phosphorus concentrations which consequently led to a reduction of 92% in chlorophyll and 85% in cyanobacterial density. With such results, the aim of the project was achieved and the classification of the lake according to Brazilian legislation for surface waters (CONAMA 357/2005) was upgraded. The trophic status of the lake improved from hypereutrophic to mesotrophic. Additionally, positive changes in the phytoplankton and zooplankton community were also observed, with an increase in the abundance of Chlorophyceae and Bacillariophyceae. As a result of these changes and the increase in Secchi depth (0.4 to 2 m), Daphnia sp were observed in the lake for the first time in decades. The success of the treatment confirms the efficiency of Phoslock® as a maintenance measure to reduce phosphorus concentrations, thereby controlling cyanobacteria, even in systems subjected to input of continuous and high organic loads.
- Combining Lake Restoration Techniques: Overview of Different Treatment Methods Used in Combination with Lanthanum Modified Bentonite (LMB)
Patrick Van Goethem
Combining Lake Restoration Techniques: Overview of Different Treatment Methods Used in Combination with Lanthanum Modified Bentonite (LMB)
Patrick Van Goethem
Phoslock Europe GmbH, Antwerp, Belgium
Phosphorus is an important nutrient for all living organisms in the aquatic food web and its concentration is a critical component in the determination of the trophic level of a water body. In fresh water systems it is often the limiting nutrient making it the primary focus of many water-quality management techniques. One of these techniques is the sequestration of water and sediment phosphate by Lanthanum Modified Bentonite (LMB). Though LMB is a tool that can be used on its own, there are situations where the use of LMB can be combined with other water-quality management techniques in order to achieve a better and/or quicker improvement of a lake.
We provide an overview of the different techniques which have been combined with the use of LMB in recent past years in order to optimise or accelerate efficiency. We also discuss the reasons for choosing a particular combination and assess the efficiency of each method based on whole lake applications.
12:00 pm – 1:30 pm
Lunch / Exhibits Open / Poster Viewing
CLM / CLP Luncheon
Clean Lakes Classic
1:30 pm – 3:00 pm
Concurrent Session F
- Developing a Conservation Strategy for Riverine Fish Habitat in Oxbow Lakes Along the Lower Wabash and White Rivers in Indiana
Developing a Conservation Strategy for Riverine Fish Habitat in Oxbow Lakes Along the Lower Wabash and White Rivers in Indiana
Cassie Hauswald1 and Brad Smith2
1The Nature Conservancy, Laconia, Indiana; 2The Nature Conservancy, Velpen, Indiana
Oxbow lakes are an important habitat type found along Indiana’s major rivers in southwest Indiana. They are an integral part of a river’s ecology. Many species of riverine fish use oxbows to reproduce or rear young. Oxbow lakes are also home to many species of rare plants, and they provide wintering and nesting habitat for waterfowl and songbirds.
Despite the ecological importance of oxbow lakes, little is known about their overall health. As a result, there have been no conservation strategies developed around this important habitat-type in Indiana. Oxbow lakes face many threats, including levees, ditching and field tiling within the lake basins, agricultural runoff, and fragmentation of surrounding woodlands.
In addition to these threats, changes in land use and hydrology in the age of European colonization have dramatically altered rates of succession in these habitats. This raises the question of the sustainability of function in the face of high sedimentation and altered flood regimes.
To establish a baseline of data and develop conservation strategies around these lakes, we completed an initial ranking process via GIS, followed by an on-the-ground sampling effort in 2017 including monthly water sampling and in 2018 fish sampling.
We will share our research results to date and discuss the challenges of developing a conservation strategy for a dynamic and large-scale habitat like oxbow lakes along the lower Wabash River.
- Reduced Oxythermal Habitat in a Two-Story Fishery: Implications for Phosphorus Management in a Northern Wisconsin Lake
Reduced Oxythermal Habitat in a Two-Story Fishery: Implications for Phosphorus Management in a Northern Wisconsin Lake
Dendy Lofton1, Hans Holmberg1, Gary Pulford2, and Dan Tyrolt3
1LimnoTech, Oakdale, Minnesota; 2Courte Oreilles Lake Assocation, Hayward, Wisconsin; 3Lac Courte Oreilles Conservation District, Hayward, Wisconsin
Lac Courte Oreilles (LCO) is a deep, 5,039-acre drainage lake in Sawyer County, Wisconsin with multiple bays and basins that support a highly valued two-story fishery. Most of the lake is classified as oligotrophic except for shallow Musky Bay, which has been characterized by eutrophic conditions as a result of elevated phosphorus loading from adjacent cranberry bogs. Recreational use of Musky Bay is impaired due to excessive aquatic plant growth and the presence of dense algal mats, as well as curly leaf pondweed. Musky Bay is a primary spawning area for muskellunge, which are currently declining in numbers likely due to poor habitat conditions and low dissolved oxygen (DO) levels in the bay. In addition, LCO is one of five inland lakes in Wisconsin that support both cisco and whitefish, which rely on optimal oxythermal conditions. Despite attainment of the current total phosphorus (TP) criteria in LCO (40 µg/L in Musky Bay; 15 µg/L elsewhere in the lake), a biologic impairment exists in the lake due to depleted DO levels in the hypolimnion, and warmer waters in the epilimnion, resulting in reduced oxythermal habitat for cisco and whitefish. Recent monitoring data shows that oxythermal habitat is reduced to a very narrow layer for these sensitive coldwater fishes in three major basins. This presentation will discuss long-term trends in TP, numeric characterization of observed DO and temperature data as an indicator of declining oxythermal habitat, and ongoing management efforts to reduce TP loading and restore musky habitat in LCO.
- Influence of Fisheries Management on Limnological Characteristics of Three Missouri Reservoirs
Influence of Fisheries Management on Limnological Characteristics of Three Missouri Reservoirs
John R. Jones and Daniel V. Obrecht
School of Natural Resources, University of Missouri, Columbia, Missouri
Dramatic fluctuations in nutrients, algal chlorophyll and suspended solids were documented over decades in three Missouri impoundments in response to basin-specific management practices to control turbidity with shoreline stabilization and aquatic vegetation with grass carp. Management was to benefit sport fisheries. Excessive vegetation in Little Dixie Lake was virtually eliminated after stocking grass carp and mineral turbidity increased (68%). Rock and water willow was used to stabilize the shoreline; mineral turbidity dropped by half and algal chlorophyll tripled, despite a decrease in total phosphorus. These changes reflect increased pelagic production. In Carl DiSalvo Lake, macrophyte removal by grass carp and herbicides triggered an alternative plankton state with increases of 3-fold in total phosphorus, 4-fold in total nitrogen, 20-fold in chlorophyll and a 5-fold decline in Secchi depth. In contrast, water willow was planted along the shoreline of Towell Lake to address mineral turbidity and within a decade, Eurasian watermilfoil covered some 70% of the surface area. Grass carp were added and currently coverage is some 30% of surface area. Between the period of turbidity and watermilfoil dominance, there were declines in both phosphorus (35%) and mineral turbidity (60%) and concurrent increase in Secchi depth (50%). Such management practices are applied statewide to benefit sport fisheries, but with less apparent changes in water quality and switches in alternative states. Such practices contribute to residual variation in cross-system analyses of nutrients relative to land cover and hydrology and could mask the benefits of best management efforts in the watershed.
- Using Baited Box Nets to Remove Common Carp to Improve Water Quality in Shallow Lakes
Using Baited Box Nets to Remove Common Carp to Improve Water Quality in Shallow Lakes
Jordan Wein1, Przemek Bajer2, and Aaron Claus1
1Carp Solutions, Saint Paul, Minnesota; 2University of Minnesota, Saint Paul, Minnesota
Common carp are present in many shallow lakes across North America and can have significant negative impacts on nutrient and water quality parameters when in large numbers. Reducing common carp biomass has been shown to increase water clarity and aquatic vegetation as well as decrease phosphorus and chlorophyll levels. Although research shows that lakes can be restored by managing carp, implementation methods have been severely hindered by lack of effective removal techniques. Traditional methods such as lake drawdowns, poisoning, and commercial seining are often ineffective, harmful to native species, cost-prohibitive, and/or rely on a few specialized contractors that are difficult to secure. An innovative method has addressed this need via baiting and trapping using custom “box net” traps. This approach is consistent with scientific findings that common carp can be trained to aggregate in specific locations using corn as bait. The chief advantage of stationary box nets is that carp can be lured into them and effectively removed, even in lakes with debris on the bottom or where carp do not form natural aggregations. Further, baiting is simple enough that citizens can be trained to administer it, increasing the scalability and affordability of this strategy. Carp Solutions conducted proof-of-concept experiments in 4 Minnesota lakes between 7 and 120 hectares in 2017 which showed that 20–50% of carp were removed from each lake using only 1–4 nets, with no non-target impacts. Managing carp can be a great challenge, but the potential benefits are multi-faceted and box netting could be one solution.
- Sediment Sampling to Assist in Evaluating Reservoir Management Methods
Sediment Sampling to Assist in Evaluating Potential Reservoir Management Methods
Kelly DiNatale1, Alex Horne2, Chris Newton1, and Andrea Terry3
1DiNatale Water Consultants, Boulder, Colorado; 2Alex Horne Associates, El Cerrito, California; 3Rivanna Water and Sewer Authority, Charlottesville, Virginia
The Rivanna Water and Sewer Authority (RWSA) is a wholesale water utility that owns and operates five reservoirs that hold drinking water supply for the City of Charlottesville and Albemarle County, Virginia. The reservoirs have experienced problems with algae blooms, which have historically been managed by the application of copper-based algaecides. Historical water quality data was limited except for the late 1970s through early 1980s and RWSA began a monitoring program in 2015 to develop a database of water quality data.
RWSA was evaluating potential reservoir and watershed management methods to improve water quality. As part of the evaluation, RWSA was seeking insight to the following questions and the associated management implications:
- Did the application of copper-based algaecides result in copper accumulation in the reservoir sediments? If there was copper accumulation that could be traced to algaecide applications, was the accumulation at concentrations that might exceed regulatory levels or otherwise trigger concerns?
- Did the diversion of effluent in one watershed in the late 1980s result in improvement in water quality? If it could be demonstrated that the reduction of inflowing nutrients results in improved water quality, it might be possible to improve water quality through reduction of nutrients within the watershed through a variety of management methods.
- Is there a significant internal nutrient flux from the reservoir sediments that should be addressed? If there was significant internal loading from accumulated reservoir sediments, management methods such as alum treatment, hypolimnetic aeration/oxygenation or dredging.
To further inform management decisions, dredge and core sediment samples were collected and analyzed in two reservoirs. Copper accumulation was detected, but at below regulatory levels. Additional watershed sampling suggested that the copper increases were likely attributable to algaecide applications. Dating and analysis of sediments showed a significant decrease in nutrients and blue-green algal pigments approximately coincident with the wastewater diversion. Nutrient fluxes were less than anticipated given the nutrient concentrations in the sediments and the length of hypolimnetic anoxia.
- A Method of Reducing Septic System Impact to Lakes
A Method of Reducing Septic System Impact to Lakes
Clear Lake Technology, Branchville, New Jersey
Lakes are affected by what happens in their watershed. Rural lake communities, for the most part, are served by on-site septic systems. The performance of these systems is highly dependent on a host of factors ranging from location, age, design, soil characteristics and proximity to ground water to the lake. Phosphorus from septic systems is often the limiting factor that controls the level of eutrophication and potential for harmful algae blooms.
Most household products no longer contain phosphorus. The main source of phosphorus is human waste. The daily production of phosphorus is about 1–1.5 grams per person. A four-person household can produce over 2 kg. of phosphorus annually. Septic systems are not perfect treatment systems and are reported to be a major cause of nutrient loading. The threat that phosphorus loading poses to lake water quality and health became the motivation behind the development of this waste water conditioning phosphorus removal system described herein.
This system developed over 4 years, has proven to eliminate over 90% of the phosphorus and coliform that would normally be discharged to a disposal field. Nominal pump out frequency is 2 to 3 years depending on septic tank size and design. The components of the conditioning system are of proven design and are currently available. No disturbance to the existing in-ground septic system is required. A managed service is needed.
Lake communities that adopt the use of this system will improve their lake’s water quality and may prevent the need for community sewers.
- A Tale of Two Watersheds: Addressing Challenges for Funding Restoration
A Tale of Two Watersheds: Addressing Challenges for Funding Restoration
Clell J. Ford
Beaver Watershed Alliance, Springdale, Arkansas
All resource managers face the challenge of acquiring funding and energizing the public in order to protect and restore regional water quality. This often means addressing the rather blunt question of “Who cares?” Garnering public and government support for source water protection is a common first step for all watersheds. Two comparable systems, Lake Istokpoga (112 km2 lake, 1554 km2 watershed), and Beaver Lake (114 km2 lake, 3087 km2 watershed), have US Army Corps of Engineers regulation schedules, are important sources of water for their respective regions, and have similar success in engaging stakeholders. However, success in funding restoration in these two regions differs greatly. Despite the status of the Istokpoga watershed as the largest source of permitted consumptive use surface water in Florida’s Kissimmee Valley, managers have struggled to identify sustainable funding for lake and watershed restoration. In contrast, the Beaver Lake watershed, which is situated in the headwaters in the Ozarks and drinking water source for more than one in seven Arkansans has sustainable funding for source water protection and watershed management activities. This talk will highlight the funding opportunities, restoration, and protection challenges faced by water resource managers for both of these watersheds. It will also shed light on future innovations in source water protection funding by exploring the possible expansion of the EPA’s clean water state revolving funds.
- Reservoir Modeling to Enhance Temperature Compliance Near a Power Plant in the Tennessee River System
Reservoir Modeling to Enhance Temperature Compliance near a Power Plant in the Tennessee River System
Rich Wildman1, Colleen Montgomery2, Jessica Brazille2, Jacob Krall1, and Rob Annear1
1Geosyntec Consultants, Portland, Oregon; 2Tennessee Valley Authority, Knoxville, Tennessee
The Tennessee Valley Authority (TVA) is responsible for managing temperature in the Tennessee River in accordance with water quality discharge permits issued to its thermal power plants. These plants withdraw cooling water from Tennessee River reservoirs and return it at increased temperatures. Discharge permits impose two regulations: 1) the absolute temperature of surface water may not exceed a specific value and 2) the temperature increase of surface water from upstream to downstream caused by a power plant may not exceed specific values. When the absolute temperature or temperature rise increases, the TVA must either activate its cooling towers or curtail power generation to ensure compliance with its permits. Both actions incur great financial cost. In this project, we sought to determine the effect of flow scenarios in a Tennessee River reservoir on surface water temperature of the reservoir at the permit compliance locations. We used CE-QUAL-W2, a two-dimensional hydrodynamic and water quality model, to evaluate a set of reservoir operation scenarios that attempt to minimize temperature increases past the power plant. Model results indicate that moderately-high summertime flow events disrupt thermal stratification and thus cool the surface water. However, this effect is greater at the upstream compliance location, and thus destratification events increase the temperature rise due to the power plant. Reduced flow events lead to warmer temperatures across the reservoir. Few scenarios were able to overcome the effects of high-wind events that de-stratify the water column upstream but not downstream and thus confound efforts to minimize temperature increase.
- Building a Financially Sustainable Early-Warning System for Harmful Algae
Building a Financially Sustainable Early-Warning System for Harmful Algae
Max Herzog1, Bryan Stubbs1, Kelli Paige2, Becky Pearson2, John Bratton3, Ed Verhamme3, Tom Johengen4, and Greg Doucette4
1Cleveland Water Alliance, Cleveland, Ohio; 2Great Lakes Observing System, Ann Arbor, Michigan; 3LimnoTech, Ann Arbor, Michigan; 4NOAA GLERL, Ann Arbor, Michigan
Harmful Algal Blooms (HABs) that occur in Lake Erie are a persistent annual problem that has threatened human health, economic stability, and ecosystem integrity in Lake Erie. Multiple federal, state, and academic groups currently monitor the western basin of Lake Erie for cyanobacterial abundance and toxicity. However, these efforts are only minimally coordinated, and samples are collected in various ways, making the comparison and integration of data difficult.
A public-private partnership comprised of Great Lakes Observing System (GLOS), Great Lakes Environmental Research Laboratory (GLERL), Cleveland Water Alliance (CWA), and LimnoTech has been awarded a three-year NOAA Ocean Technology Transfer grant to implement and commercialize an integrated monitoring solution to this challenge. The team will leverage the current real-time observing network for HABs, to drive key technologies through the transitional stages between research and full operations in order to ensure that they are sufficiently mature for long-term operations.
Additionally, the project engages with stakeholder input and collaboration with the goal of creating and stabilizing a reliable funding and operations plan for a Lake Erie Harmful Algal Blooms Data Management and Communication support structure for 1) an existing operational real‐time sensor network whose components are owned and operated by Ohio drinking water utilities and their contractors, and 2) a related research sampling and monitoring network in Lake Erie. This will allow stakeholders optimized access to critical monitoring data to help inform management decisions that are affected by the presence of HABs, as well as making this information available to the general public.
- Monitoring Cyanobacteria in Mixed Algal Populations in an Effort to Predict the Onset of CyanoHABs
Monitoring Cyanobacteria in Mixed Algal Populations in an Effort to Predict the Onset of CyanoHABs
Turner Designs, San Jose, California
Global occurrence of CyanoHABs is increasing at an alarming rate sparking a need for development of new methods and tools to rapidly quantify, monitor, and mitigate bloom events. Countless annual timelines have been recorded showing increased bloom activity at a certain time of the year, “hot” season, followed by relaxation period. During a “hot” season, when bloom activity is expected to peak, we’re preparing for sampling and analysis in an effort to better characterize the factors leading to the onset of HABs. During the relaxation period there may also be short lived HAB events stemming from changes such as increased anthropogenic input or anomalous heat spikes. These off-peak bloom events may offer better information for determining the driving factors behind HABs, but are hard to catch using in situ fluorometers that specifically monitor cyanobacterial marker pigments such as phycocyanin (PC), which only provide a partial answer to the question, “Is a HAB fast approaching?” A more detailed approach using high frequency, field-ready tools such as the CyanoFluor or PhytoFind, which use pigment ratios, allows us to rapidly monitor cyanobacteria populations WITHIN total algal populations providing information which can be used to predict the onset of HABs and offering valuable data for building predictive models. This is the best approach to help further our understanding of why HABs occur.
- Working Towards a Forecast of Lake Erie Cyanobacterial Bloom Toxicity
Working Towards a Forecast of Lake Erie Cyanobacterial Bloom Toxicity
Justin Chaffin1, John Bratton2, Tom Bridgeman3, Tim Davis4, Greg Dick5, Kevin Meyer5, Ed Verhamme2, Judy Westrick6, and Pengfei Xue7
1Ohio State University, Put in Bay, Ohio; 2LimnoTech, Ann Arbor, Michigan; 3University of Toledo, Toledo, Ohio; 4Bowling Green State University, Bowling Green, Ohio; 5University of Michigan, Ann Arbor, Michigan; 6Wayne State University, Detroit Michigan; 7Michigan Technological University, Houghton, Michigan
Lake Erie has been plagued by Microcystis blooms since the late 1990s. In recent years, a seasonal bloom forecast has been issued in early July based on the spring phosphorus load from the Maumee River. Although bloom size and location can be reasonably well forecasted, questions remain about the controls and predictability of microcystins (MC) concentrations in blooms. One complexity in field studies has been the coexistence of toxic and non-toxic strains of Microcystis. The factors influencing the dynamics of toxic and non-toxic strains within blooms are only beginning to be understood, but they may be at the point where reasonable predictions of changes in MC concentrations could be possible. While phosphorus has a clear role in bloom dynamics, nitrogen may also be important in the occurrence and biomass of cyanobacteria and the toxicity within the blooms. Other factors, such as light intensity and temperature, may also interact with nitrogen to impact MC production. This presentation will present 1) historical (since 2014) MC and cyanobacterial biomass correlations from 4758 samples collected between June and October in the western basin, 2) numerical models of ecological and physical processes to develop hindcasting, nowcasting, and forecasting capabilities, and 3) field and laboratory experiments that show the influence of nitrogen, light, and temperature on MC production and biodegradation rates. We are working with NOAA to incorporate the results of this project into forecasting operational systems.
- Lake Champlain’s Cost-Effective and Successful Cyanobacteria Monitoring Program
Lake Champlain’s Cost-effective and Successful Cyanobacteria Monitoring Program
Angela Shambaugh1, Bridget O’Brien2, Lori Fisher3, and Heather Campbell1
1Vermont Department of Environmental Conservation, Montpelier, Vermont; 2Vermont Department of Health, Burlington, Vermont; 3Lake Champlain Committee, Burlington, Vermont
Lake Champlain lies between Vermont, New York and the province of Quebec in Canada. In 1999, the lake experienced its first known toxic cyanobacteria bloom when two dogs died after ingesting cyanobacteria. Nuisance blooms had been documented in parts of the lake since the late 1970s, but there was limited information regarding cyanobacteria composition or seasonal dynamics at the time. Entities already active on Champlain rapidly formed a partnership to monitor cyanobacteria conditions during the summer recreation period. This strong partnership has grown over the last 15 years, utilizing qualitative and quantitative data collected by citizen volunteers and state staff.
The monitoring approach is based on visual cues that can be used by anyone anywhere to evaluate cyanobacteria condition and impact on recreational activities. Selected stations also provide quantitative data on cyanotoxins and phytoplankton densities. Weekly reports provided by trained observers between mid-June and late September are shared via an online tracking map and weekly email updates. Rapid communication of bloom conditions to state and local health officials in each jurisdiction facilitates response at the local level according to their established procedures. Together, this system has become a cost-effective and successful approach to monitor cyanobacteria on a very large, multijurisdictional lake.
- The Effects of Invasive Species in Kentucky Lake (USA) as Documented by Long-Term Monitoring
The Effects of Invasive Species in Kentucky Lake (USA) as Documented by Long-Term Monitoring
David White1, Susan Hendricks1, and Bommanna Loganathan2
1Hancock Biological Station, Murray State University, Murray, Kentucky; 2Department of Chemistry, Murray State University, Murray, Kentucky
While limited populations of silver carp (Hypophthalmichthys molitrix) and zebra mussels (Dreissena polymorpha) have existed for more than 25 years in Kentucky Lake (Tennessee River), both species had not become truly invasive until quite recently. Our understanding of the mechanisms behind silver carp’s explosive growth are inadequate at this time. Zebra mussels became “invasive” in 2017 and can be associated with changes in dissolved calcium levels between 2012 and 2017 that now exceed the 21–23 mg per liter threshold for their establishment. Both invasives are planktivorous and appear to be linked with changes in Secchi depth, turbidity, plankton community structure, alkalinity, and primary productivity as shown by the 30-year Kentucky Lake Long-Monitoring Program database. Secchi depth (m) has slowly increased since 1988 from about 1 m to 1.5 m with several readings well over 3 m in recent years. Turbidity has slowly decreased from 15 NTUs in 1988 to averages now around 4 NTUs. Commensurate with turbidity, there have been decreases in zooplankton, phytoplankton, and primary production, but surprisingly, levels of chlorophyll a have remained fairly constant. Changing lake conditions have trophic level implications for native planktivores, especially freshwater mussels, shad, paddlefish, and larval stages of most fish species. As the monitoring program continues, we should be able to better document long-term changes in food web dynamics linked to these and other invasive species.
- Constraints on Curlyleaf: An Evaluation Curlyleaf Pondweed Biology and Management through Analysis of Monitoring Data from Across Organizations
★ Michael Verhoeven
Constraints on Curly-Leaf: An Evaluation of Curly-Leaf Pondweed Biology and Management Through Analysis of Monitoring Data from Across Organizations
Michael R. Verhoeven, Daniel J. Larkin, and Raymond M. Newman
University of Minnesota Department of Fisheries, Wildlife and Conservation Biology & Minnesota Aquatic Invasive Species Research Center, St. Paul, Minnesota
Curly-leaf pondweed (Potamogeton crispus) is one of the most widespread and problematic invasive aquatic plants in the Great Lakes region. Despite decades of research and treatment efforts, there is still uncertainty about best practices for treating curly-leaf pondweed and the influence of environmental factors, such as trophic state and winter conditions, on curly-leaf populations. To address these gaps, we synthesized and analyzed data from 252 point-intercept surveys of 51 lakes collected from 2006–2015. Nineteen lakes had data for years treated with herbicide (65 treatment lake-years) and 41 lakes had data for untreated years (116 untreated lake-years). We used generalized linear mixed models to estimate the influence of environmental drivers and herbicidal treatments on curly-leaf lake-level distribution (frequency of occurrence) and abundance (relative rake density). We found that greater winter snow cover, water clarity, and herbicide treatment were associated with reductions in lake-wide distribution of curly-leaf pondweed. We parsed the effects of herbicides based on three temporal windows and found that curly-leaf pondweed distribution was reduced within the year of treatment, the year following treatment, and by cumulative years of treatment. In contrast, curly-leaf pondweed abundance was not affected by environmental variables, and only by a within-year effect of herbicide treatment. Our results show that increasing long-term consistency of herbicide-based management may allow for lower annual management inputs, and that environmental conditions should be considered in management planning. This project highlights the power of combining monitoring data from across organizations to support collective learning and adaptive management.
- Wisconsin’s Strategy for Prevention of Aquatic Hitchhikers
Wisconsin’s Strategy for Prevention of Aquatic Hitchhikers
Susan Graham and Amanda Smith
Wisconsin Department of Natural Resources, Madison, Wisconsin
Aquatic invasive species, otherwise known as AIS, are non-native species that can take over, spread primarily by humans, and negatively impact recreation, the economy, and our native ecosystems. Given the scale of the problem and the threat, this presentation will describe what Wisconsin is doing, how we encourage citizens to partner with scientists, and what success has looked like here. Wisconsin has a comprehensive rule called NR-40 that classifies species that are prohibited, restricted, or not a concern, and guides regulations based on risks. In addition to containment and control, we employ a multi-faceted approach to prevent the introduction and spread of AIS. For the Wisconsin DNR, preventing the spread of invasive species relies on a social science understanding of human behavior.
- Deep in the Weeds of Aquatic Plant Management in New Jersey's Delaware and Raritan Canal
Deep in the Weeds of Aquatic Plant Management in New Jersey’s Delaware and Raritan Canal
Chris J. Doyle1, Jon Gosselin2, Heather Desko3, Emily R. Mayer1,4, and Mark A. Heilman5
1SOLitude Lake Management, Washington, New Jersey; 2SePRO Corporation, Manchester, New Hampshire; 3New Jersey Water Supply Authority, Clinton, New Jersey; 4University of Florida, Gainesville, Florida; 5SePRO Corporation, Carmel, Indiana
Dense aquatic vegetation growth affects the ability of New Jersey’s Delaware and Raritan Canal to transfer 100 Million Gallons of Water a Day (100 MGD) from the Delaware River to meet the demands of drinking water treatment facilities and golf courses on its way to the Raritan River. In 2016, the vegetation was so dense, the New Jersey Water Supply Authority contracted for conventional mechanical raking to reduce submersed aquatic plant growth, only to discover several miles of Hydrilla verticillata growth. This finding led to the development of an Aquatic Plant Management Plan, 60 miles of canal submersed aquatic vegetation mapping, a low-dose herbicide application, and an intensive monitoring plan to manage the infestation. This presentation will cover the treatment, mapping, and monitoring response that the New Jersey Water Supply Authority initiated in 2017, plus an update on the 2018 continuing efforts.
- Lake Mauvaise Terre Nutrient and Sediment Reduction Initiative
Lake Mauvaise Terre Nutrient and Sediment Reduction Initiative
Northwater Consulting, Springfield, Illinois
Lake Mauvaise Terre lies within Morgan County, Illinois, has a surface area of approximately 170 acres and serves as a back-up source of drinking water for the City of Jacksonville and surrounding communities. The watershed area for Lake Mauvaise Terre is 21,402 acres, primarily made up of agricultural row crops which are responsible for 70% of the total lake sediment load. Mauvaise Terre is impaired for total suspended solids, total phosphorus, and total nitrogen. A Total Maximum Daily Load (TMDL) plan finalized in 2011 indicated that a substantial reduction in both internal and external loads was required to meet the State’s 0.05 mg/L phosphorus standard. Unfortunately, the TMDL lacked specifics on implementation strategies and locations. This prompted the development of a Watershed Implementation Plan with support from the American Farmland Trust and the City of Jacksonville. Using targeted field assessments, modeling, and one-on-one landowner outreach, a series of locations were identified that represented the primary sources of sediment and phosphorus. The City partnered with a selection of landowners and an EPA Section 319 grant application was submitted. The $650,000 grant was approved in 2015 and used for the survey, design, and construction of hundreds of individual Best Management Practices. The initiative achieved a 4.3% reduction in total nitrogen, a 7% reduction in total phosphorus and a 12% reduction in sediment. The presentation will highlight key aspects of the watershed planning process, meaningful pollutant source assessment, landowner negotiations, the grant application, BMP design and construction considerations, and results.
- Response of a Reservoir Ecosystem to Changes in Watershed Agriculture Over Two Decades
Response of a Reservoir Ecosystem to Changes in Watershed Agriculture Over Two Decades
Michael Vanni, William Renwick, Maria Gonzalez, Patrick Kelly, and Tanner Williamson
Miami University, Oxford, Ohio
We present 24 years of data on the response of eutrophic Acton Lake to changes in watershed agriculture. Over the first decade, the use of conservation tillage increased greatly in the watershed. This led to large decreases in suspended sediment (SS) and P (soluble and particulate) concentrations in inflow streams and decreased (discharge-adjusted) loads of SS and P to the lake. However, during the second decade, stream SS declined at a slower rate, and soluble P actually increased. In contrast, stream nitrate changed little over the first decade, but declined sharply in the second decade. In Acton Lake, phytoplankton biomass increased markedly over the first decade, despite decreased inputs of P from streams. The phytoplankton increase was probably because declining lake SS concentrations alleviated phytoplankton light-limitation, and because of increasing biomass (and hence nutrient excretion rate) of detritivorous fish, specifically gizzard shad. Over the second decade, phytoplankton biomass showed no temporal trend. However, phytoplankton N-limitation became more common, whereas P was usually limiting in the first decade. This shift toward increasing N limitation is associated with declining stream N:P ratios and a greater importance of internal loading from fish excretion, which has relatively low N:P. Our long-term data reveal complex, temporal scale-dependent responses of a reservoir ecosystem to changing watershed agriculture. In addition, our data show that internal nutrient cycling by fish, and reduced light limitation, provide resilience against reversing eutrophication.
- Upstream Collaboration and Investment Achieves Downstream Protection
Upstream Collaboration and Investment Achieves Downstream Protection
City of Boulder, Public Works, Boulder, Colorado
Barker Reservoir is a primary water supply for the City of Boulder, with storage capacity of up to 11,000 acre-ft. A small wastewater treatment facility (WWTF) with an average flow of 0.14 MGD contributes < 1% of the reservoirs average annual inflows, yet prior to 2013 was responsible for 65% of the total phosphorus (TP) and 40% of the total nitrogen loading. The WWTF was exempt from TP limits due to size, but basic upgrades from the aerated lagoon system were required to achieve ammonia limits in a revised discharge permit.
Seeing the opportunity to invest in the WWTF to protect Barker Reservoir from eutrophication, water treatment challenges, and taste and odor issues, Boulder provided $300,000 in capital funding for WWTF TP removal, and annual financial support ($17,300 adjusted annually for inflation) through 2024.
Since the 2013 WWTF upgrades, effluent TP concentrations have decreased 10-fold resulting in improved reservoir water quality. Average reservoir TP decreased from 19.6 to 12.4 μg/L, and biologically available forms of nutrients have also decreased: ortho-P decreased by 53% and total Kjeldahl nitrogen decreased by 23%. Although not statistically significant, reservoir chlorophyll a decreased from 7.7 to 6.9 μg/L. Chlorophyll a is a nutrient response variable and reductions may take longer to detect.
Investing in upstream WWTF upgrades improved water quality in the city’s primary source water reservoir and has allowed the city to maintain conventional water treatment. Further, the investment has better positioned the upstream community for meeting future nutrient controls.
- Changes in Grand Lake St. Marys Watershed: Moving Towards an Improved Understanding of Water Quality Over the Past Decade
Stephen J. Jacquemin
Changes in Grand Lake St. Marys Watershed: Moving Towards an Improved Understanding of Water Quality Over the Past Decade
Stephen J. Jacquemin
Wright State University – Lake Campus, Celina, Ohio
Grand Lake St Marys (GLSM) is a hypereutrophic lake situated in the primarily agricultural GLSM watershed of northwest Ohio. Over the past decade, numerous surveys have characterized the environmental quality of the lake as highly impaired. Elevated nutrient rich runoff levels coupled with the physical characteristics of the watershed have acted as catalysts for frequent harmful algal blooms resulting in no contact warnings and drinking advisories which have impacted the region environmentally and economically. In 2011, the watershed was officially declared distressed by the state of Ohio. Following this designation, a series of voluntary and obligatory best management practices, conservation initiatives, and rules were implemented in an effort to reduce nutrient loading on a watershed scale. These efforts included constructing wetlands and in-lake littoral areas, increasing the use of filter strips, riparian buffers, cover crops, improving manure management practices, such as transferring manure out of the watershed and increasing covered manure storage, and the implementation and enforcement of policies encompassing the maintenance of nutrient management plans and a watershed wide ban on winter manure application. Since 2011, nitrogen and phosphorus concentrations have greatly declined during the winter months (16–57%) as well as the remainder of the year (12–41%; with exception of spring SRP) during critical medium and high flow loading periods. Despite these impressive declines, however, nutrient levels remain too high. Thus, conservation work in GLSM is ongoing and includes the continued expansion of existing BMPs as well as addition of new wetlands to continue improving water quality region wide.
3:00 pm – 3:30 pm
Refreshment Break / Exhibits Open / Poster Viewing
3:30 pm – 5:00 pm
Concurrent Session G
- Coolwater Fish Habitat in a Changing Climate
3D Modeling and Prediction of Coolwater Fish Habitat in a Changing Climate
Water Resources Team, University of Minnesota Extension, Farmington, Minnesota
Climate change impacts the physical, chemical, and biological processes of aquatic ecosystems. Future fish habitat conditions are predicted to change both their temporal and spatial distributions. The ability to predict the fish habitat with fine spatial and temporal resolutions can facilitate and target fish management strategies that can reduce the undesirable impacts of climate change. We investigated the temporal and spatial (both vertical and horizontal) variability of fish habitat dynamics at a fine scale by using a 3D lake water quality model. We implemented a measured historical scenario and two predicted future climate change scenarios developed by applying the change fields to the two measured scenarios; results and the methods used will be presented. Water temperature (T) and dissolved oxygen (DO) were selected as key water quality parameters to evaluate the changes in coolwater fish habitat, where T increased 4 °C and DO decreases 1 mg L-1 during the ice-free seasons under the future climate scenarios. The onset of stratification increased 46 days, thermocline depth increased 64%, and the onset of anoxia occurs 4 weeks earlier. For the first time, we will report the 3D changes of T and DO defining fish habitat in a Minnesota lake. The desirable good growth fish habitat was separated for three weeks in July by the lethal fish habitat, leaving the coolwater fish with no potential refuge. The spatial and temporal prediction of stressed or lethal environmental conditions along with forecasting the potential fish refuge areas is essential in water resources and ecological management.
- The Feasibility of Restoring Lake Whitefish as an Integral Component of the Cold-Water Fish Community in Otsego Lake, New York
★ Samantha Carey
The Feasibility of Restoring Lake Whitefish as an Integral Component of the Cold-water Fish Community in Otsego Lake, New York
Samantha Carey1, Kevin C. Thomas2, Daniel T. Garrett2, Brent C. Lehman2, John R. Foster2, Mark D. Cornwell2, Scott Wells3, and Daniel S. Stich1
1State University of New York, Oneonta, New York; 2State University of New York, Cobleskill, Cobleskill, New York; 3New York State Department of Environmental Conservation, R4 Stamford Fisheries, Stamford, New York
Lake Whitefish (LWF), a key component of the cold-water fish fauna of Otsego Lake was decimated by the introduction of Alewife (Alosa pseudoharengus) in the 1980s. With the recent collapse of the Alewife in this system, the restoration of the historically important LWF population is now feasible. A collaborative effort to enhance LWF in Otsego Lake is now underway, involving the New York State Department of Environmental Conservation, the State University of New York (SUNY) at Cobleskill, and the SUNY Oneonta Biological Field Station. Project objectives are to 1) document LWF spawning locations and population dynamics, and 2) supplement the population through field spawning, egg rearing and stocking of fry and fingerlings. Electrofishing, trap netting and fry emergence traps identified three spawning locations in the lake. The LWF produced in the Endangered Fish Hatchery at SUNY Cobleskill will help restore an important Otsego Lake fishery and balance the lake’s cold-water fish community by enhancing the lake trout forage base.
- Hydropower Retrofits at Non-Powered Dams: Trends in Environmental Mitigation
Hydropower Retrofits at Non-Powered Dams: Trends in Environmental Mitigation
Miles Mobley, Joey Werble, Adam Witt, and Patrick O’Connor
Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee
The United States currently utilizes more than 80,000 non-powered dams (NPDs)—dams that do not produce electricity—to provide a variety of services ranging from water supply to inland navigation. As the United States seeks to increase renewable energy generation, hydroelectric retrofits of NPDs have become an attractive option for two reasons: the use of existing hydraulic infrastructure lowers the total installed cost of the project, and many of the environmental impacts of development have already been incurred. Many of the NPDs currently slated for development are navigation dams that form pools in navigable waterways, and the protection, enhancement, and mitigation measures and costs associated with such NPD retrofits have not been well established.
This presentation will summarize an analysis of federally required environmental mitigation measures and associated costs from over 70 NPD retrofits licensed by the Federal Energy Regulatory Committee (FERC) within the last 15 years, with an emphasis on riverine NPD development. Measures and costs were gathered from formal environmental assessments, largely reflecting the consensus outcomes of detailed studies and negotiations among project stakeholders. Cataloging the types of mitigation requirements (e.g., aquatic resources, water quality, recreation resources, threatened and endangered species, etc.) by dam purpose (e.g., lock and dam) can provide valuable insight to hydro developers and lake managers who want to investigate the possibility of adding hydroelectric capabilities to existing NPDs.
- Kicking the tires on the new 3D water quality model AEM3D
Kicking the Tires on the New 3D Water Quality Model AEM3D
Barr Engineering Company, Minneapolis, Minnesota
Given the expense of restoring lakes to a quality acceptable for many uses such as recreation and drinking water, it is becoming more important to better understand lake dynamics and make more accurate predictions of a whole host of water quality parameters, not just phosphorus. For some systems, a three-dimensional model is needed but there are very few that are available. The Aquatic Ecosystem Model (AEM3D), built by Hydronumerics in Australia, is a newly available model based upon the ELCOM-CAEDYM model developed at the University of Western Australia. This presentation shows the results of an AEM3D model that was built for Sweeney Lake in Golden Valley, Minnesota. The purpose of this modeling effort was to evaluate the effect of aeration in Sweeney Lake on phosphorus, phytoplankton, and dissolved oxygen in the lake. Using AEM3D, a comparison was made between the relative effectiveness of alum treatment and aeration.
- Continuous Lake Monitoring Buoy – Lessons Learned from the First Year
Continuous Lake Monitoring Buoy – Lessons Learned from the First Year
Kiyoko Yokota and Paul H. Lord
State University of New York College at Oneonta / Biological Field Station, Oneonta, New York
Continuous lake monitoring buoys, or lake data buoys, once mainly developed and used by academic researchers, are gaining popularity within the greater lake management communities, including municipal utility operators and individual lake associations. These buoys log and transmit high-frequency data that reveal previously unnoticed spatial and temporal patterns in physical, chemical and biological processes in lakes and reservoirs. Established commercial vendors are capable of configuring a system that meets specific monitoring needs of a given site; however, the actual deployment method and maintenance needs are highly site specific and need to be carefully planned and executed by the local project managers. We present a case study from Otsego Lake, a glacial mesotrophic lake (maximum depth ≈ 51 m or 168 ft) in Central New York State, where we completed the first cycle of deployment, winterization and re-deployment of our NSF-funded data buoy in 2017–2018 as part of the Global Lake Ecological Observatory Network (GLEON). System configuration processes, initial and recurring cost, data management and analysis will also be covered.
- Aquatic Effects Monitoring for the Meliadine Mine
Aquatic Effects Monitoring for the Meliadine Mine
Colleen Prather, Elaine Irving, Suzanne Earle, and Zsolt Kovats
Golder Associates Ltd., Edmonton, Alberta, Canada
The Meliadine Gold Mine is located in the Kivalliq District of Nunavut in Northern Canada, and approximately 25 km north of the community of Rankin Inlet. The Aquatic Effects Monitoring Program (AEMP) is a requirement of the licence to operate the Mine. The AEMP was structured as a comprehensive monitoring program with the overall objective to assess potential mine related effects on water quality, sediment quality, benthic invertebrates, plankton, and fish of Meliadine Lake.
Pre-construction activities were completed at the Mine in 2015 and 2016, and construction activities were initiated in October 2016; discharge of mine generated effluent (the main pathway that can affect the aquatic environment) was initiated in June 2018. The AEMP is an annual monitoring program and data collected in 2015 through 2017 were evaluated to characterize the aquatic environment before effluent discharge. Data collected starting in 2018 through operations (i.e., while the Mine is discharging effluent) will be used to characterize effects to the aquatic environment.
Meliadine Lake is a large lake with a surface area of 107 km2, a highly convoluted shoreline of 465 km, over 200 islands, and a watershed area of 560 km2. Development in the watershed is limited to a few cabins, resource exploration, and the Mine.
This presentation will provide details of the integrated aquatic effects study design, a summary of data collected since 2015, ecological interpretations of the data, and next steps in aquatic effects monitoring at this location.
- Influence of Environmental Factors on Off-Flavor Metabolite Production by Bacteria in a Eutrophic Reservoir
★ Nicolas Clercin
Influence of Environmental Factors on Off-Flavor Metabolite Production by Bacteria in a Eutrophic Reservoir
Nicolas A. Clercin1,2 and Gregory K. Druschel1
1Department of Earth Sciences, Indiana University – Purdue University, Indianapolis, Indiana; 2Center for Earth and Environmental Science (CEES), Indianapolis, Indiana
The community structure of bacterioplankton in a dimictic and eutrophic drinking water supply reservoir was characterized by PCR amplification using the V3 and V4 regions of the 16S rRNA. Bacterial communities were recovered from different depths (0, 3, 6 and 10 m) within the water column through time (April to October). Meanwhile, the physical properties of the water column were measured in situ as well as the water chemistry for major anions and two odorous bacterial metabolites, 2-methylisoborneol (MIB) and geosmin. In average, dominant bacterial groups were Cyanobacteria (36%), Proteobacteria (25%) and Actinobacteria (7%). A cross correlation linked a major peak discharge to highest detections of both MIB and geosmin after a 37-day delay. Geosmin detections were strongly correlated to occurrences of Cyanobacteria (Planktothrix spp., p < 0.001) that was growing in the reservoir waters while MIB led to the Actinobacteria (Streptomyces spp., p < 0.01). Application of a copper-based algaecide treatment terminated Cyanobacteria and disrupted the geosmin production whereas it was not so effective against Actinobacteria and MIB. A Canonical Correspondence Analysis (CCA) shows that taste-and-odor (T&O)-causing bacteria are more abundant when the water is enriched with nitrogen, temperature cooler and, the water column fully mixed and oxygenated.
- Understanding the Effect of Salinity Tolerance on Cyanobacteria Associated with a Harmful Algal Bloom in Lake Okeechobee, Florida
Understanding the Effect of Salinity Tolerance on Cyanobacteria Associated with a Harmful Algal Bloom in Lake Okeechobee, Florida
Barry Rosen1, Keith Loftin2, Jennifer Graham2, Katherine Stahlhut1, James Riley3, Brett Johnston1, and Sarena Senegal2
1US Geological Survey, Orlando, Florida; 2US Geological Survey, Lawrence, Kansas; 3US Army Corps of Engineers, Jacksonville, Florida
In an effort to simulate the survival of cyanobacteria as they are transported from Lake Okeechobee to the estuarine habitats that receive waters from the lake, a bioassay encompassing a range of salinities was performed. An overall decline in cyanobacteria health in salinity treatments greater than 18 practical salinity units (psu) was indicated by loss of cell membrane integrity based on SYTOX® Green staining, but this loss varied by the kind of cyanobacteria present. Microcystis aeruginosa was tolerant of salinities up to 18 psu; however, higher salinities caused leaking of microcystin from the cells. Dolichospermum circinale, another common bloom-former in this system, did not tolerate salinities greater than 7.5 psu. Stimulation of mucilage production was observed and is likely a mechanism used by both species to protect organism viability. At 7.5 psu, and to some extent at 10 psu, microcystin increased relative to chlorophyll a, providing some evidence of biosynthesis when M. aeruginosa is stressed at these salinities. At 15 psu or greater, the particulate microcystin concentration relative to chlorophyll a is diminished, although additional research would be needed to determine the exact effect of salinity on this relation.
- Potential Linkage Between Zebra Mussel Establishment, Cyanobacterial Community Composition and Microcystin Levels in the United States Lakes
Potential Linkage Between Zebra Mussel Establishment, Cyanobacterial Community Composition and Microcystin Levels in United States Lakes
Feng Zhang1, Song Liang2,3, Ozeas Costa4 and #Jiyoung Lee5,6
1Environmental Science Graduate Program, The Ohio State University, Columbus, Ohio; 2Department of Environmental and Global Health, University of Florida, Gainesville, Florida; 3Emerging Pathogens Institute, University of Florida, Gainesville, Florida; 4School of Earth Sciences, The Ohio State University at Mansfield, Mansfield, Ohio; 5College of Public Health, Division of Environmental Health Sciences, The Ohio State University, Columbus, Ohio; 6Department of Food Science and Technology, The Ohio State University, Columbus, Ohio
Zebra mussel invasion of northern American lakes during the last century may play an important role in the occurrence of toxic cyanobacteria blooms. Herein, large-scale data from the USEPA National Lake Assessment (> 1,000 lakes) were used to study the potential linkage between zebra mussels, cyanobacteria community composition, and cyanotoxin levels in the lakes. ANOVA Based on Dissimilarities tests (Adonis) showed that there was a significant difference in cyanobacterial communities between lakes located in areas with and without established zebra mussel populations. Meanwhile, significantly higher microcystin levels and cyanobacteria abundance were observed, but lower concentrations of phosphorous in lakes located in areas with established zebra mussels. Structural equation modeling was used to confirm and estimate the effect of zebra mussels on microcystin concentrations via different pathways. The results suggest three potential pathways whereby zebra mussels influence microcystin production: 1) altering phosphorous concentration; 2) increasing cyanobacteria abundance; and 3) shifting cyanobacteria community structure. The total effect of zebra mussel establishment resulted in an overall 1.40 times net increase in microcystin level, which presumably resulted from three contributing factors: 1) a 1.06 times increase through an increased cyanobacteria abundance; 2) a 1.53 times increase through a selective force, resulting in increased cyanobacteria toxicity; and 3) a 0.86 times decrease in microcystin level through total phosphorus decrease. The study suggested the important potential role of zebra mussel invasion in altering cyanobacterial composition and influencing microcystin levels in the US lakes.
- Cyanobacterial Combat: The Battle to Manage pH in a Naturally-Acidic Groundwater-Fed Lake
Cyanobacterial Combat: The Battle to Manage pH in a Naturally-Acidic Groundwater-Fed Lake
Diane Lauritsen1 and Linda Ehrlich2
1Envirochem, Wilmington, North Carolina; 2Spirogyra Diversified Environmental Services, Burlington, North Carolina
White Lake is a shallow, groundwater-fed natural lake located in North Carolina’s Coastal Plain. It is one of a number of distinctive Bay Lakes found in the region, with an elliptical shape and elevated sand rim. While most of the Bay Lakes are acidic, blackwater systems, White Lake has been very acidic (pH levels 4.2–4.4 SU) but clear, and the water clarity and sandy shoreline have made it a very popular recreational lake for generations of North Carolinians. Within the past decade there has been a decline in the clarity of the water and a dramatic change in its acidity; there are now periods in which the water is not acidic, but basic, as a result of elevated productivity and the very low alkalinity of the water. With the changing of the lake chemistry from acidic to basic, conditions favoring harmful cyanobacteria and the invasive aquatic weed Hydrilla were established. A cyanobacterial bloom, dominated by the filamentous Planktolyngbya limnetica, developed in late summer 2017 which greatly affected water clarity, and chlorophyll a levels exceeded the state standard of 40 mg/L for the first time. The bloom persisted into the spring of 2018, and by early May the mean algal biovolume was 151,577 mm3/m3, mean chlorophyll a was 52 mg/L, and the Secchi depth was 0.5 m. As a result, pH levels increased substantially (9.1–9.6 SU) throughout the lake. The Town of White Lake received approval to arrange for and fund an in-lake treatment with alum to flocculate and remove algae and nutrients from the water column, and the treatment was completed by mid-May. The alum treatment significantly reduced pH levels, gradually and significantly improved water clarity, eliminated the two filamentous cyanobacteria (Aphanizomenon was the second-dominant taxon in early May) and reduced levels of both N and P. Given the long residence time, the apparent increase in both external and internal nutrient loading rates, the productivity-pH feedback loop, and more frequent extreme weather events such as Hurricane Florence, White Lake will likely be at risk for future cyanobacterial blooms that could significantly impact ecosystem health and public use of the lake. The challenge will be to develop consensus and a spirit of collaboration among stakeholders as further management options are assessed.
- A Day in the Life
A Day in the Life
Stephen J. Souza
Princeton Hydro, LLC, Ringoes, New Jersey
It is difficult to believe that my career in applied limnology started over 35 years ago! My first NALMS conference was the 3rd Symposium held in Knoxville, Tennessee in 1984. Throughout the years NALMS has always played a significant role in how I went about studying and managing lakes. My career has been exclusively within the private sector. However, that gave me the opportunity along the way to conduct work for a very diverse client base consisting of private, public, NGO and governmental entities.
My career has had a number of milestone moments, but the two that were the most significant were joining the start-up company Coastal Environmental and forming Princeton Hydro. Both involved a substantial amount of risk and uncertainty but were driven by the need to “do the right thing.” This “Voice of Experience” presentation deals with the challenges of working as a consultant in the private sector. The presentation deals with how the foundation of commercial success is built upon conducting good science, maintaining a moral compass, and having the ability to adapt your business model to a changing business environment. It also discusses how doing so is key to developing and nurturing long-term relationships with clients.
- 40+ Years of Rowboat Limnology: What a Ride!
40+ Years of Rowboat Limnology: What a Ride!
Water Resource Services, Wilbraham, Massachusetts
I never intend to truly retire; lake work is too much fun, but I have cut back substantially in 2018. It feels like the long slow-down straightaway at the end of a rollercoaster ride; the exhilaration of the ride is still fresh, and it is not over, but I no longer have the anticipation I had at the start. I am one of those rare people who knew what they wanted to do from an early age and did it. I lived across the street from a lake in New Jersey until I was 13 and was fascinated by everything aquatic from an early age. I studied algae even before I went to college and worked for the NJDEP lakes program for 4 years before expanding my biological horizons at grad school. I went to work in consulting at the start of 1985 and worked for successively larger firms until 2010 when I started WRS, always working on water issues and usually on lakes or reservoirs. It has never been boring. I started out typically naïve and idealistic, thinking I could play with algae and bugs, promote “green” solutions and not really deal much with people. A lot of other professionals made me a much better lake manager over time. I will relate key things I learned along the way, including that lake management is about people more than lakes and that you should never answer a work phone after 2 PM on a Friday!
- 67 Years of Streams, Lakes, Reservoirs and Oceans: A Wet Life!
67 Years of Streams, Lakes, Reservoirs and Oceans: A Wet Life!
University of California, Berkeley, California
Like Ken Wagner, my ecological interests started early, but in coal, steel, and railways-dominated industrial northern England not Jersey. From 1951-3, I made drawings depicting the changes in location of rooks (colonial crows) nests in large deciduous trees. Only 8 years old, I was innocent of statistics but discovered that rooks were faithful to their locations even though winter winds destroyed the nests. Sadly, I also observed how, but not why, acid coal mine slag heap runoff restricted sticklebacks in local streams. And I remember England’s “Silent Spring” though more due to the decline in butterflies I collected than songbirds. A biochemistry major, my graduate career started in 1964 taking samples of blue-green algae (cyanobacteria) in eutrophic Mutton Chop Pond on Hampstead Heath in London. Research on nitrogen and carbon fixation lead me to the English Lake District, Antarctic oceans and wetlands, African lakes, and California. In 1970, consulting and research in the US included lakes, reservoirs, rivers, estuaries, and coastal and tropical oceans in all 7 continents – over 500 projects to date! Recent projects include lake and reservoir restoration with oxygenation, dredging, aeration, and biomanipulation, wetlands construction for targeted pollution removal and oil pollution in the Gulf of Arabia. I have learned a lot, but three concepts are relevant for NALMS members. They are (1) A hidden key (2) A least worse choice and (3) Patience.
- Some Stormwater Ponds Release Phosphorus
★ Vinicius Taguchi
Some Stormwater Ponds Release Phosphorus
Vinicius Taguchi1, Tyler Olsen2, John Gulliver1, Ben Janke3, Poornima Natarajan1, and Jacques Finlay4
1St. Anthony Falls Laboratory, Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Minneapolis, Minnesota; 2Barr Engineering, Minneapolis, Minnesota; 3St. Anthony Falls Laboratory, Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, Minnesota; 4Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, Minnesota
Stormwater retention ponds are ubiquitous in many urban landscapes but are not given much consideration post-construction. High total phosphorus (TP) concentrations from pond grab sample data for 98 ponds in Minnesota suggest that urban stormwater ponds may be releasing phosphorus (P) to receiving water bodies due to high internal loading. This is alarming because retention ponds are one of the most frequently implemented stormwater control measures (SCMs) targeting phosphorus removal. Laboratory incubations of intact sediment and water cores from 5 ponds suggest that mobile-P concentrations (iron-bound P, loosely-bound P, and labile organic P) in pond sediments and sediment oxygen demand (Smax) are indicators of P release potential. Actual P release was measured under anoxic (dissolved oxygen (DO) < 1 mg/L) conditions and was observed to be negligible under oxic conditions (DO > 1 mg/L). However, in-situ field monitoring revealed that several shallow stormwater ponds in the Twin Cities Metro Area are so strongly stratified during the spring and summer months as to prevent diurnal mixing and reoxygenation of the water column from periodic storm events. Conductivity profile measurements suggest that this is likely due to chemostratification from chlorides applied as road salt during the winter months. The resulting anoxic conditions at the sediment-water interface throughout much of the year would facilitate P release into the water column and subsequently downstream receiving water bodies.
- Utilizing EPA Green Infrastructure Toolkit to Evaluate Potential Management Strategies for an Urban Watershed
★ Monica Matt
Utilizing EPA Green Infrastructure Toolkit to Evaluate Potential Management Strategies for an Urban Watershed
State University of New York College at Oneonta Biological Field Station, Cooperstown, New York
The internet provides countless resources for scientists, lake managers, and educators. One such resource includes the Green Infrastructure Modeling Toolkit by the US Environmental Protection Agency (EPA). This collection of 5 downloadable programs and 1 online application can help individuals to better understand green infrastructure, compare environmental outcomes with various stormwater management techniques, and design watershed best management practices (BMPs). Each computer program is unique and requires different levels of technical expertise, geospatial data, and amount of defined physical parameters. Utilization of these innovative programs will aid the development of potential watershed and stormwater management practices for Lake Ronkonkoma, New York. The lake is located in Suffolk County and is the largest lake on Long Island. The watershed is predominantly residential and developed; green infrastructure practices in this area may assist future efforts to reduce runoff volume and external nutrient loading.
- Ecosystem Service Assessment of Stormwater Management Features in Greater Cleveland
Ecosystem Service Assessment of Stormwater Management Features in Greater Cleveland
Julie Wolin and Brittany Dalton
Cleveland State University, Cleveland, Ohio
Greater Cleveland is focused on improving Lake Erie water quality and capturing stormwater runoff in neighborhoods. Stormwater management has been incorporated into green and complete street designs, and repurposed vacant lands. This provides an opportunity to assess the efficacy of green infrastructure in stormwater capture, and the ecosystem services and societal benefits created (i.e., increased biodiversity, pollinator habitat, reduced urban heat island effects, improved neighborhood recreation or aesthetic value). We assessed surrounding land use and maintenance practices in green infrastructure throughout Greater Cleveland. Site visits were conducted for 164 bioretention and rain gardens. Sites were assessed for physical characteristics, surrounding land use, and overall function, including level of erosion and exposed soils. An initial survey recorded all plants present, including invasive species, and each site was revisited for a final plant survey. We analyzed invasive species presence, maintenance practices, and resident awareness and acceptance. The presence of invasive plants can impact the ability of green infrastructure to function properly and provide the ecosystem services as originally intended. Invasive species presence was correlated with increased impervious surface, surrounding land use dominated by human activities, and poor maintenance practices. We also found residents were often unfamiliar with the purpose of rain gardens and bioswales. Improper care and maintenance resulted in the loss of beneficial plants and provided an avenue for invasive species. Resident perception varied widely. Some viewed stormwater management systems as weedy and unkempt, thus affecting the potential for widespread use.
- The State of the Lake: Communicating Watershed Science and Engaging Stakeholders in the Lake Champlain Basin
The State of the Lake: Communicating Watershed Science and Engaging Stakeholders in the Lake Champlain Basin
Lake Champlain Basin Program, Grand Isle, Vermont
Lake Champlain, often termed the “sixth great lake” is an important ecological and economic resource for stakeholders in New York, Vermont, and Quebec. Since the founding of the Lake Champlain Basin Program, the organization has worked to communicate the condition of the Lake to these stakeholders: one tool for this communication is the State of the Lake and Ecosystem Indicators Report, released every three years. The 2018 State of the Lake focused on four goals for the Lake and Basin: clean water, healthy ecosystems, thriving communities, and an informed and involved public. The report presents the most recent information on the conditions of Lake Champlain and its watershed, including phosphorus loading, cyanobacteria and beach closures, mercury in fish tissue, invasive species, flooding, and climate change, and highlights the results of some of the management actions undertaken in the Basin. This document serves as a record of the status of the Lake and provides public stakeholders with an opportunity for education and engagement. This presentation will discuss the research, analysis, writing, and design necessary to compiling this document, and the uses it has in the watershed.
5:00 pm – 9:00 pm
NALMS Awards Reception and Banquet