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SACRAMENTO MODEL—(Hydrology) A dynamic River Flow Model or Water Budget Model, run on a computer at various intervals, which accounts for all water entering, stored in, and leaving a Drainage Basin. Though many parameters are used in this water balance accounting process, precipitation has the main impact on runoff.

SACRAMENTO-SAN JOAQUIN DELTA [California]—See Bay-Delta [California].

SACRIFICIAL ANODE—An easily corroded material deliberately installed in a pipe or intake to give it up to corrosion while the ret of the water supply facility remains relatively corrosion-free.

SAFE DRINKING WATER ACT [SDWA] (Public Law 93-523)—An amendment to the Public Health Service Act which established primary and secondary quality standards for drinking water. The SDWA was passed in 1976 to protect public health by establishing uniform drinking water standards for the nation. In 1986 SDWA Amendments were passed that mandated the U.S. Environmental Protection Agency (EPA) to establish standards for 83 drinking water contaminants by 1992 and identify an additional 25 contaminants for regulation every 3 years thereafter. See Drinking Water Standards, Drinking Water Standards [Nevada], Primary Drinking Water Standards, and Secondary Drinking Water Standards. [Also see Appendix D-5, Nevada Drinking Water Standards.]

SAFE WATER—Water that does not contain harmful bacteria, toxic materials, or chemicals, and is considered safe for drinking even if it may have taste, odor, color, and certain mineral problems.

SAFE YIELD—The rate at which water can be withdrawn from supply, source, or an aquifer over a period of years without causing eventual depletion or contamination of the supply. More commonly referred to a Perennial Yield and Sustained Yield. Generally consists of the rate of Natural Recharge, Artificial (or Induced) Recharge, and Incidental Recharge.

SAG PIPE—A section of a sewer line that is placed deeper in the ground than normal in order to pass under utility piping, waterways, rail lines, highways, or other obstacles. The sewer line is raised again after passing under the obstacle. Also referred to as Inverted Siphon.

SAG POND—(1) A small body of water occupying an enclosed depression or sag formed where active or recent fault movement has impounded drainage. (2) (California) One of many ponds and small lakes along the San Andreas Fault.

SALINA—(1) A salt marsh, spring, pond, or lake. (2) An area of land encrusted with salt.

SALINATION—The process whereby soluble salts accumulate in the soil.

SALINE—(1) Term used to describe waters containing common salt, or sodium chloride. (2) Of or containing any of the salts of the alkali metals or magnesium.

SALINE/POOR QUALITY AQUIFER—An aquifer containing water that is high in total dissolved solids, and is unacceptable for use as drinking water.

SALINE MARSH—A saturated, poorly drained area, intermittently or permanently water covered, having aquatic and grasslike vegetation whose water chemistry contains various dissolved salts.

SALINE SEEPS—Wet areas in non-irrigated soils where soluble salts accumulate from the evaporation of the seeping water and crop or grass production is reduced or eliminated.

SALINE SODIC LAND—Soil that contains soluble salts in amounts that impair plant growth but not an excess of exchangeable sodium.

SALINE SOIL—A nonalkali soil containing soluble salts in such quantities that they interfere with the growth of most plants.

SALINE WATER—Water containing dissolved solids; generally referring to solid contents in excess of 1,000 parts per million (ppm) Total Dissolved Solids (TDS). The U.S. Geological Survey (USGS) classifies the degree of salinity of these more mineralized bodies of water as follows:

[1] Slightly Saline—1,000-3,000 ppm;
[2] Moderately Saline—3,000-10,000 ppm;
[3] Very Saline—10,000-35,000 ppm; and
[4] Brine—More than 35,000 ppm.

SALINITY—The relative concentration of salts, usually sodium chloride, in a given water sample. It is usually expressed in terms of the number of parts per thousand (0/00) or parts per million (ppm) of chlorine (Cl). Although the measurement takes into account all of the dissolved salts, sodium chloride (NaCl) normally constitutes the primary salt being measured. As a reference, the salinity of seawater is approximately 35 0/00. See Salts for comparative salt concentrations in water. Also see Total Dissolved Solids.

SALINITY CONTROL—The physical control, management, and use of water and related land resources in such a way as to maintain or reduce salt loading and concentrations of salt in water supplies.

SALINITY INTRUSION—The movement of salt water into a body of fresh water. It can occur in either surface water or ground water bodies.

SALINIZATION—The accumulation of salts in soil to the extent that plant growth is inhibited. This is a common problem when crops are irrigated in arid regions; much of the water evaporates and salts accumulated in the soil. Also see Leaching Requirement.

SALMONELLA TYPHOSA—A waterborne microorganism which is the causative agent of typhoid fever.

SALMONELLOSIS—The bacterial disease caused by the presence of bacteria of the genus Salmonella. The disease is a type of food poisoning characterized by a sudden onset of gastroenteritis involving abdominal pain, diarrhea, fever, nausea, and vomiting. A variety of foods, such as sweets, meats, sausages, and eggs, can be the mode of infection. Pet turtles and birds can also transmit the bacteria.

SALT—A chemical class of ionic compounds formed by the combination of an acid and a base. Most salts are the result of a reaction between a metal and one or more nonmetals. See Salts, below.

SALTATION—Particle movement in water or wind where particles skip or bounce along the stream bed or soil surface.

SALT BALANCE—A condition in which specific or total dissolved solids removed from a specified field, stratigraphic zone, political area, or drainage basin equals the comparable dissolved solids added to that location from all outside sources during a specified period of time.

SALT FLAT—A salt-encrusted flat area resulting from evaporation of a former body of water.

SALT LAKE—A landlocked body of water that has become salty through evaporation.

SALT MARSH—Low areas adjacent to the sea that are covered with salt-tolerant vegetation (Halophytes) and regularly flooded by the high tide. As part of the Wetland systems, such areas help to stabilize shorelines and prevent erosion from tide and wave actions. Also, similar inland areas near saline springs or lakes, though not regularly flooded.

SALT PAN—An undrained natural depression in which water gathers and leaves a deposit of salt on evaporation.

SALTS—Salts are the minerals that water picks up as it passes through the air, over and under the ground, and through household and industrial uses. A compound composed of the positive ion from a base and the negative ion from an acid; i.e., a metal ion and a nonmetal ion, such as KBr (Potassium Bromide). The proportions or concentrations of salts