Comparing Futures for the Sacramento - San Joaquin Delta

Glossary

glossary adaptive management A flexible, learning-based management approach in which natural systems are managed to ensure their recovery and improvement , while an understanding of how these systems function is developed to raise the effectiveness of future management actions. anadromous fish species Fish that live in ocean water and move inland to spawn, such as salmon. beneficiary pays principle The principle that financial responsibility for a project is apportioned among those who benefit from it. consumptive water use Diversions of water withdrawn but not returned downstream. cumulative probability The total probability over a range of values or time periods. desirable fish species Fish with at least two of the following attributes: (a) listed as threatened or endangered, or proposed for listing, under state or federal Endangered Species Acts; (b) support an important sport or commercial fishery; (c) endemic or native; and (d) dependent on the estuary to complete their life cycle, either by living there or migrating through it. electrical conductivity A surrogate measurement for salinity in water. environmental water Water allocated to support fish and aquatic habitat, often through minimum flow requirements. estuary A semi-enclosed embayment where salt water is significantly diluted by fresh water from inflowing rivers. 203 export diversions Water diverted from the Delta watershed for use in areas to the west and south of the Delta. export pumps Pumps used for water exports, primarily in the southern Delta. fish entrainment The drawing of fish or fish larvae into pumps or water diversions. fishery The organized capture of fish for sport or commercial purposes. ground acceleration A measure of intensity of shaking during an earthquake, often described as proportional to the acceleration due to gravity. groundwater banking The managed storage of water in underground aquifers. hydraulic factors The effect of water movement on biological and physical processes. hydrologic conditions Conditions related to water inflows. hydrodynamic The physics of water movement and the movement of matter (e.g., sediment and salts) in the water. indirect exports Water diverted from the Delta watersheds (mainly in the SacramentoValley and on the east side of the San JoaquinValley) before the water reaches the Delta. Upstream diversions are a form of indirect exports. inflows Natural or managed flows of water into a particular location. interties or intertied water system Connections between water conveyance facilities. An intertied water system such as California’s is quite flexible and cost effective in accommodating water shortages or malfunctions at specific water management facilities. land subsidence The sinking of lands caused by compaction, oxidation of peat soils, and wind erosion. Many Delta islands have subsided (mostly from oxidation and erosion) to the point at which they now lie many feet below sea level. minimum flow requirements Water flows required by regulators, typically for environmental purposes. mitigation An action intended to moderate some effects of other activities. For instance, flood management agencies often make one-time payments (known as “flood easements”) to property owners in areas that will be allowed to flood periodically to help cover the costs of flooding. outflow Flows of water going away from a particular location. pelagic fish species Fish that live their entire life in open water, above the bottom. Within the Delta, this category includes delta smelt, longfin smelt, and striped bass. glo ssary 204 pl 84-99 standards Minimal standards for levee construction in the Delta to qualify for federal assistance in repairs and rehabilitation. reclamation The diking and draining of swamplands. Most “reclaimed” Delta lands are used for agriculture, although some lands are used for wildlife habitat and urban development. salinity The concentration of salt in water. As a rough guide, seawater is 35 parts per thousand (ppt)(grams per liter) and fresh water is less than 3.0 ppt. Drinking water is less than 1.0 ppt. tidal excursions The mixing of waters caused by daily tidal movements into and out of an estuary. unimpaired flows Streamflows unaffected by upstream dams, diversions, or return flows. upstream diversions Water diverted from the Delta watersheds (mainly in the SacramentoValley and on the east side of the San JoaquinValley) before the water reaches the Delta. Upstream diversions are a type of indirect export. water diversions The withdrawal of water from a water body, some of which might be returned downstream after use. water exports Generally refers to water used somewhere other than its area of origin. Direct Delta exports refers to water...