The San Diego Bay Watersheds Common Grounds Project was created to incorporate data from water quality monitoring programs and integrate this data on a watershed level using a web-based interactive application to serve as a broad communication, education and decision-making tool; and to further develop the region's capacity to understand and assess processes affecting our water resources.


303(d) List – Under Section 303(d) of the 1972 Clean Water Act, states, territories and authorized tribes are required to develop a list of water quality limited segments. These waters on the list do not meet water quality standards, even after point sources of pollution have installed the minimum required levels of pollution control technology. The law requires that these jurisdictions establish priority rankings for water on the lists and develop action plans, called as Total Maximum Daily Loads (TMDL), to improve water quality. (California State Water Resources Control Board:

 Aluminum (Al) – Aluminum is a chemical element. It is one of the most abundant elements in the earth's crust and occurs in many rocks and ores, but never as a pure metal. The presence of aluminum ions in streams may result from industrial wastes but is more likely to come from the waste water of drinking water treatment plants. Waters containing high concentrations of aluminum can become toxic to aquatic life if the pH is lowered (as in acid rain). (Kentucky Water Watch:

 Ammonia – Ammonia (NH3) is found in surface water, in the soil, and as a byproduct of decaying plant tissue and decomposition of animal waste. Ammonia is rich in nitrogen and an excellent fertilizer. If ammonia levels in water are too high, fish can experience ammonia toxicity. (Cech (2005) Principles of Water Resources)

 Analyte – A substance measured in the laboratory. A chemical for which a sample (such as water, air, or blood) is tested in a laboratory. For example, if the analyte is mercury, the laboratory test will determine the amount of mercury in the sample. (The Agency for Toxic Substances and Disease Registry:

 Anthropogenic – Anthropogenic effects or processes are those that are derived from human activities, as opposed to effects or processes that occur in the natural environment without human influences. (Wikipedia:

 Aqueduct – A pipe, conduit, or channel designed to transport water from a remote source, usually by gravity. (USGS:

 Aroclors – Industrial chemicals which have become persistent environmental pollutants in soil and water. Aroclors are Polychlorinated biphenyls (PCBs) and can bioconcentrate in aquatic animals and affect human health. (EPA:

 Arsenic – Arsenic is a highly toxic metal found naturally in the environment and as an industrial and agricultural byproduct. Long-term exposure to the metal can lead to cancer and has adverse effects on cardiovascular, pulmonary, immunological, neurological and endocrine systems. As of January 23, 2006, the EPA has set the arsenic standard for drinking water 10 parts per billion. (EPA:

 Bacteriological – Of or relating to bacteriology, the science and study of bacteria and their relation to medicine and to other areas such as agriculture (e.g., farm animals) and industry. (Medical Dictionary:

 Bay Protection and Toxic Cleanup Program (BPTCP) - In 1989, the California State Legislature established the Bay Protection and Toxic Cleanup Program (BPTCP). The BPTCP has four major goals: (1) to provide protection of present and future beneficial uses of the bays and estuarine waters of California; (2) identify and characterize toxic hot spots; (3) plan for toxic hot spot cleanup or other remedial or mitigation actions; (4) develop prevention and control strategies for toxic pollutants that will prevent creation of new toxic hot spots or the perpetuation of existing toxic hot spots in the bays and estuaries of the State. (California State Water Resources Control Board:

 Benthic organisms – The group of organisms inhabiting the bottom of the aquatic environment. They include a number of types of organisms, such as bacteria, fungi, insect larvae and nymphs, snails, clams, and crayfish. They are useful as indicators of water quality. (USGS:

Biochemical Oxygen Demand – A measure of the quanity of dissolved oxygen, in milligrams per liter, ncessary fo the decompostion of organic matter by microorganisms, such as bacteria. (USGS:

Boron – Occurs as sodium borate (borax) or as calcium borate (colemanite) in mineral deposits and natural waters of southern California. Boron is not considered harmful in drinking waters in concentrations up to 30 mg/l. Boron is an essential element for the growth of plants but there is no evidence that it is required by animals. Naturally occurring concentrations of boron should have no effect on aquatic life. (San Diego Basin Plan:

 Calcium – Calcium is a chemical element. Calcium salts and calcium ions are among the most commonly occurring in nature. They may result from the leaching of soil and other natural sources or may come from man-made sources such as sewage and some industrial wastes. Calcium is usually one of the most important contributors to hardness. Even though the human body requires approximately 0.7 to 2.0 grams of calcium per day as a food element, excessive amounts can lead to the formation of kidney or gallbladder stones. High concentrations of calcium can also be detrimental to some industrial processes. Thus, both domestic and industrial water users have to consider calcium concentrations. Calcium also serves an important role in the health of bodies of water. In natural water it is known to reduce the toxicity of many chemical compounds on fish and other aquatic life (Kentucky Water Watch:

 Chemical Oxygen Demand (COD) – A measure of the chemically oxidizable material in the water and furnishes an approximation of hte amount of organic and reducing material present. The determined value may correlate with biochemical oxygen demand or carbonaceous organic pollutio form sewage or industrial wastes. (USGS:

 Chlordane – A manufactured chemical that was used as a pesticide in the United States from 1948 to 1988. The EPA has found potential long-term and short-term health effects for humans and has been found to bioaccumulate in aquatic animals. (EPA:

 Chloride - A salt compound resulting from the combination of the gas chlorine and a metal. Some common chlorides include sodium chloride (NaCl) and magnesium chloride (MgCl2). Chlorine alone as Cl2 is highly toxic, and it is often used as a disinfectant. In combination with a metal such as sodium it becomes essential for life. Small amounts of chlorides are required for normal cell functions in plant and animal life.  Sources include rocks containing chlorides, agricultural runoff, wastewater from industries, oil well wastes, and effluent wastewater from wastewater treatment plants. (Kentucky Water Watch:

 Clean Water Act (CWA) - Growing public awareness and concern for controlling water pollution led to enactment of the Federal Water Pollution Control Act Amendments of 1972. As amended in 1977, this law became commonly known as the Clean Water Act. The Act established the basic structure for regulating discharges of pollutants into the waters of the United States. It gave EPA the authority to implement pollution control programs such as setting wastewater standards for industry. The Clean Water Act also continued requirements to set water quality standards for all contaminants in surface waters. The Act made it unlawful for any person to discharge any pollutant from a point source into navigable waters, unless a permit was obtained under its provisions. It also funded the construction of sewage treatment plants under the construction grants program and recognized the need for planning to address the critical problems posed by nonpoint source pollution. (EPA:

 Conductivity – Electrical conductivity estimates the amount of total dissolved salts (TDS), or the total amount of dissolved ions in the water (Water on the Web:

 Contaminant – A chemical of biological substance in a form that can be incorporated into, onto, or be ingested by and that harms aquatic organisms, consumers of aquatic organisms, or users of the aquatic environment. (San Diego Basin Plan: )

 Copper – An essential nutrient, required by the body in very small amounts. However, short-term exposure can potentially cause nausea and long-term exposure can cause liver or kidney damage. Copper mining and smelting operations and corrosion of copper pipes in the home are the major sources of copper in water. (EPA:

 Costa-Machado Water Act of 2000 (Proposition 13) – The Costa-Machado Water Act of 2000, Coastal Nonpoint Source Control Program provides funding for projects that restore and protect the water quality and environment of coastal waters, estuaries, bays, and near shore waters and groundwater. (California State Water Resources Control Board:

 DDT –The first chlorinated hydrocarbon insecticide chemical name: Dichloro-Diphenyl-Trichloroethane. It has a half-life of 15 years and can collect in fatty tissues of certain animals. EPA banned registration and interstate sale of DDT for virtually all but emergency uses in the United States in 1972 because of its persistence in the environment and accumulation in the food chain. (EPA:

 Diazinon – Diazinon is a mobile and moderately persistent man-made pesticide in the environment. Due to its chemical properties and its widespread use, diazinon is frequently found in wastewater treatment plant effluent and urban and agricultural runoff. Diazinon is toxic to aquatic life, particularly invertebrates. On December 31, 2004, it became illegal to sell diazinon products for residential use in the United States. It is still lawful to use diazinon properly under the Federal Insecticide, Fungicide and Rodenticide Act for non-residential agricultural or other uses. Even so, phasing out the residential uses of diazinon should significantly reduce the amount of this pollutant that enters surface waters (EPA:

 Dissolved Organic Carbon (DOC) – DOC is used to describe the thousands of dissolved compounds found in water that derive from organic materials (such as decomposed plant matter). DOC is organic material from plants and animals broken down into such a small size that it is “dissolved” into water. Some DOC molecules have a recognizable chemical structure that can easily be defined (such as fats, carbohydrates, and proteins) however most have no readily identifiable structure and are lumped under the term humic or tannin substances (

 Dissolved Oxygen – The molecular oxygen (oxygen gas) dissolved in water. The concentration in water is a funcation of atmospheric pressure, temperature, and dissolved-solids concentration of the water. The ability of water to retain oxygen devreases with increasing temperature or dissolved-solids concentration. Photosynthesis and respiration by plants commonly cause diurnal (day/night) variations in dissovled oxygen contration in water from some streams. (USGS:

 Dry Weather Flow – The flow in a system that occurs during dry weather, without a stormwater component. In these systems dry-weather flow may include one or all of the following: sanitary wastewater; pre-treated industrial wastewater; unauthorized industrial wastewater; groundwater that has infiltrated or leaked into the system; latent or delayed stormwater flows through the vadose zone that have leaked into the system; chemical and sanitary landfill leachate; lawn irrigation runoff; foundation drainage; washwater such as from cars and industrial sites; unauthorized disposal of oil and hazardous chemicals; and other miscellaneous entries. (EPA:

 Enterococcus – Bacteria commonly found in the feces of humans and other warmblooded animals. Although some strains are ubiquitous and not related to fecal pollution, the presence of enterococci in water is an indicator of fecal pollution and the possible presence of enteric pathogens. (USGS:

 Escherichia coli (E. coli) – Bacteria present in the intestine and feces of warmblooded animals. E. coli are a member species of the fecal coliform group of indicator bacteria. Their concetrations are expressed as number of colonies per 100 mL of sample.(USGS:

 Ethyl Parathion – Ethyl parathion is an organophosphate insecticide and miticide registered for use on nine agricultural crops: alfalfa, barley, corn, cotton, canola, sorghum, soybean, sunflower, and wheat. Ethyl parathion can cause cholinesterase inhibition in humans and animals; that is, it can overstimulate the nervous system causing nausea, dizziness, confusion, and, at very high exposures (e.g. accidents, major spills), respiratory paralysis and death (EPA:

 Fecal Coliform – Bacteria present in the intestines or feces of warmblooded animals. They are often used as indicators of the sanitary qualiy of the water. Their concentrations are expressed as number of colonies per 100 mL of sample. (USGS:

 Geographic Information System (GIS) – GIS is a collection of computer hardware, software, and geographic data for capturing, managing, analyzing, and displaying all forms of geographically referenced information. (ESRI:

 Hardness – A physical-chemical characteristic of water created by the amount of dissolved minerals, such as calcium, magnesium, and iron present in the water. ‘Hard’ water is sometimes described as the inability to create a lather when washing. Hardness of water can be a factor in degenerative cadrdiovascular disease such as heart disease, hypertension and stroke, possibly caused by the corrosive aspects of soft water to the heavy metals in pipes. The degree of hardness is expressed as the equivalent concentration of calcium carbonate (CaCO3). (Cech (2005) Principles of Water Resources)

 Heavy Metals – Metallic elements with high atomic weights (i.e. mercury, chromium, cadmium, arsenic, and lead).  They can damage living organisms at low concentrations and tend to accumulate in the food chain. (EPA:

 Heptachlor – A non-agricultural insecticide. The Environmental Protection Agency has banned most uses of the product since 1978 but it continues to persist in the environment. Exposure to heptachlor has been linked to increased liver damage and increased risk of cancer. (EPA:

 Impaired water body – Water bodies that do not meet established water quality standards and are listed on the EPA 303(d) list (see 303(d) List).

 Malathion – Malathion is an organophosphate pesticide that is toxic to aquatic organisms, and data confirm that exposure can exceed the level of concern for many aquatic invertebrate species. Concentrations in water can occur as a result of drift or from runoff in urban areas (EPA:

 Mercury (Hg) – Mercury, also called quicksilver, is a chemical element. Mercury is a bioaccumulative toxin. It is a naturally occurring element that can be toxic when consumed by animals and humans. Sources of mercury include weathering of the earth's crust, the burning of garbage and fuels, and industrial emissions. (EPA:

 Metadata – Information that describes the content, quality, condition, origin, and other characteristics of data or other pieces of information. Metadata for spatial data may describe and document its subject matter; how, when, where, and by whom the data was collected; availability and distribution information; its projection, scale, resolution, and accuracy; and its reliability with regard to some standard. Metadata consists of properties and documentation. Properties are derived from the data source (for example, the coordinate system and projection of the data), while documentation is entered by a person (for example, keywords used to describe the data). (ESRI:

 Methylene Blue Activated Substances (MBAs) – The MBAs test measures the presence of anionic surfactant (commercial detergent) in water. Positive test results can be used to indicate the presence of domestic waste water. (San Diego Basin Plan:

 Methyl Parathion – Methyl parathion is an insecticide that does not occur naturally in the environment. Methyl parathion interferes with the normal way that the nerves and brain function.  It is toxic to both humans and aquatic life (Agency for Toxic Substances and Disease Registry (ATSDR):

 Naphthalene – A volatile organic compound (VOC) that is naturally present in fossil fuels such as petroleum and coal, and is produced when wood or tobacco are burned. Naphthalene is used in the production of many products, including dyes, pharmaaceuticals, and insect repellents, such as moth balls. Releases of naphthalene to the environment are widespread. In humans, exposure to large amounts of naphthalene may damage or destroy red blood cells, causing hemolytic anemia. (EPA:

 Nickel (Ni) – Nickel is a metallic chemical element. Very small amounts of nickel have been shown to be essential for normal growth and reproduction in some species of animals. Nickel and its compounds can have high acute and chronic toxicity to aquatic life. Nickel toxicity to aquatic organisms is determined by water hardness - the softer the water, the higher the toxicity. Finely divided particles of nickel and nickel compounds are mainly carried by air. Contributions to the atmosphere come from both natural sources and human activity. Nickel occurs naturally in surface waters from the weathering of minerals and rocks (Australian Government, Department of the Environment and Heritage:

 Nitrate – A compound containing nitrogen that can exist in the atmosphere or as a dissolved gas in water and which can have harmful effects on humans and animals. Nitrates in water can cause severe illness in infants and domestic animals. A plant nutrient and inorganic fertilizer, nitrate is found in septic systems, animal feed lots, agricultural fertilizers, manure, industrial waste waters, sanitary landfills, and garbage dumps. (EPA:

 Non-point source runoff – pollution discharged over a wide land area, not from one specific location. Non-point source pollution is contamination that occurs when rainwater, snowmelt, or irrigation washes off plowed fields, city streets, or suburban backyards. As this runoff moves across the land surface, it picks up soil particles and pollutants, such as nutrients and pesticides. (USGS:

 Organic carbon (OC) – A measure of organic matter present in aquaeous solution, suspension, or bottom sediment. May be reported as dissolved organic carbon (DOC), particulate organic carbon (POC), or total organic carbon (TOC). (USGS:

 Organophosphorus Pesticides – Most organophosphates are insecticides. Organophosphates were developed during the early 19th century, but their effects on insects, which are similar to their effects on humans, were discovered in 1932. Some are very poisonous. However, they usually are not persistent in the environment. Organophosphates affect the nervous system by reducing the ability of cholinesterase, an enzyme, to function properly in regulating a neurotransmitter called acetylcholine. Acetylcholine helps transfer nerve impulses from a nerve cell to a muscle cell or another nerve cell. If acetylcholine is not properly controlled by cholinesterase, the nerve impulses or neurons remain active longer than they should, over stimulating the nerves and muscles and causing symptoms such as weakness or paralysis of the muscles. (EPA:

 PCB Congeners - Any single, unique, well-defined chemical compound in the PCB category is called a "Congener".  The name of a congener specifies the total number of chlorine constituents and the position of each chlorine. (EPA: (see Polychlorinated biphenyls)

 pH – pH of water is the negative logarithm of the hydrogen-ion activity. Solutions with pH less than 7.0 standard units are termed "acidic," and solutions with a pH greater than 7.0 are termed 'basic.' Solutions with a pH of 7.0 are neutral. The presence and concentration of many dissolved chemical constituents found in water are affected, in part, by the hydrogen-ion activity of water. Biological processes including growht, distribution of organisms, and toxicity of the water to organisms also are affected, in part, by the hydrogen-ion activity of water. (USGS:

 Phosphorus – A common nutrient found in soil and water, that is quickly bound to soil particles or consumed by plants. Excess phosphorus often indicates pollution from fertilizer, animal wastes, wastewater treatment plants and dish soap from leaking septic systems. Phosphorus can cause excessive growth of algae (algal blooms) which can effect water quality and aquatic life. (Cech (2005) Principles of Water Quality)

 Polychlorinated biphenyls (PCBs) – Polychlorinated biphenyls (PCBs) are a family of man-made chemicals that contain 209 individual compounds with varying levels of toxicity. Some are recognized carcinogens. Eating contaminated fish is a major source of PCB exposure for humans because PCBs bioaccumulate in some species of fish found in contaminated waters. PCBs were widely used as coolants and lubricants in transformers, capacitors, and other electrical equipment until they were banned in 1977. Although PCBs are no longer manufactured, exposure still occurs as a result of historical contamination and the decommissioning of older transformers and capacitors, which have lifetimes of 30 years or more (Scorecard, The Pollution Information Site:

 Polycyclic Aromatic Hydrocarbons (PAHs) - PAHs are a group of chemicals that are formed during the incomplete burning of coal, oil, gas, wood, garbage, or other organic substances, such as tobacco and charbroiled meat. There are more than 100 different PAHs. PAHs generally occur as complex mixtures (for example, as part of combustion products such as soot), not as single compounds. PAHs usually occur naturally, but they can be manufactured as individual compounds for research purposes; however, not as the mixtures found in combustion products. Studies in animals have also shown that PAHs can cause harmful effects on skin, body fluids, and the body's system for fighting disease after both short- and long-term exposure. (Agency for Toxic Substances and Disease Registry (ATSDR):

 Project Swell – Project SWELL (Stewardship: Water Education for Lifelong Leadership) teaches our children about the importance of our recreational waterways and human-water interaction through a well-balanced, comprehensive and hands-on water quality and pollution prevention curricula. (San Diego Coastkeeper:

 Query – A request to select features or records from a database. A query is often written as a statement or logical expression. (ESRI:

 Regional Water Quality Control Board (RWQCB) – There are nine Regional Water Quality Control Boards (Regional Boards) in the state of California. The mission of the Regional Boards is to develop and enforce water quality objectives and implementation plans that will best protect the beneficial uses of the State's waters, recognizing local differences in climate, topography, geology, and hydrology.  Each Regional Board has nine part-time members appointed by the Governor and confirmed by the Senate.  Regional Boards develop ‘basin plans’ for their hydrologic areas, govern requirements, issue waste discharge permits, take enforcement action against violators, and monitor water quality. (California State Water Resources Control Board:

San Diego Basin Plan – The San Diego Regional Board’s Basin Plan is designed to preserve and enhance water quality and protect the beneficial uses of all regional waters.  Specifically, the Basin Plan (1) designates beneficial uses for surface and ground waters; (2) sets narrative and numerical objectives that must be attained or maintained to protect the designated beneficial uses and conform to the State’s antidegradation policy; (3) describes implementation programs to protect the beneficial uses of all waters in the Region; and (4) describes surveillance and monitoring activities to evaluate the effectiveness of the Basin Plan. (California State Water Resources Control Board, Region 9:

 SDSU – San Diego State University, member of the Cal State University public school system. (San Diego State University:

 Shapefiles – A vector data storage format for storing the location, shape, and attributes of geographic features in a Geographic Information System (GIS). (ESRI:

Standard Urban Stormwater Mitigation Plan (SUSMP) – On December 13, 2001, the Regional Water Quality Control Board issued a Municipal Storm Water National Pollutant Discharge Elimination System Permit (NPDES Permit No. CAS004001) that requires new development and redevelopment projects to incorporate storm water mitigation measures, effective September 2, 2002. Depending on the type of project, either a Standard Urban Stormwater Mitigation Plan (SUSMP) or a Site Specific Mitigation Plan is required to reduce the quantity and improve the quality of rainfall runoff that leaves the site. Developers are encouraged to begin work on complying with these regulations by visiting the Watershed Protection Division (WPD) in the design phase of their projects. (

State Water Resources Control Board (SWRCB) – The State Water Resources Control Board (State Water Board) was created by the Legislature in 1967. The joint authority of water allocation and water quality protection enables the State Water Board to provide comprehensive protection for California's waters.  The State Water Board consists of five full-time salaried members, each filling a different specialty position. Board members are appointed to four-year terms by the Governor and confirmed by the Senate. (California State Water Resources Control Board:

 Static maps – Static maps are map image files. You cannot directly interact with static maps as you do with streaming maps. These maps can be previewed online and then downloaded for use on your computer. (Geography Network:

 Stormwater – Stormwater discharges are generated by runoff from land and impervious areas such as paved streets, parking lots, and building rooftops during rainfall and snow events that often contain pollutants in quantities that could adversely affect water quality. (EPA:

 Surface Water Ambient Monitoring Program (SWAMP) – For decades, water quality data have been collected and recorded, but the difficulties have arisen in the development of systems or standards to streamline methodologies and provide a standardized format that allows for data sharing within and beyond the regional scope. Often times, following data collection, this information is not shared amongst other water quality practitioners and interested parties beyond its being published in a final report. SWAMP is a state initiative that integrates surface water quality monitoring data at the state and regional levels and with other monitoring programs in California . SWAMP allows the State Water Quality Control Board to assess the water quality data in order to work to meet the objectives of the Clean Water Act. This is done with an emphasis on two primary platforms: quality assurance and data management.  SWAMP serves to form a bridge not only between the nine Regional Water Quality Control Boards operating in the state, but it also ensures that data collected by municipalities, private companies and non-profit organizations all is of a certain level of quality and that the data that is presented can be integrated into other systems for ease of use. Furthermore, SWAMP works to operate with other agencies concerned with water quality objectives - California Environmental Data Exchange Network (CEDEN), Total Daily Maximum Loads (TMDL), and with California water quality tracking programs already in operation. 

Synthetic Pyrethroids – Synthetic pyrethroids are a group of hydrophobic compounds with significant aquatic toxicity. They are synthetic chemical insecticides that act in a similar manner to pyrethrins, which are derived from chrysanthemum flowers (EPA:

 Total Coliform – Total Coliforms are a group of closely related, mostly harmless bacteria that live in soil and water as well as the gut of animals. The extent to which total coliforms are present in the source water can indicate the general quality of that water and the likelihood that the water is fecally contaminated (EPA:

 Total Maximum Daily Load (TMDL) – A Total Maximum Daily Load, or TMDL, is a regulation designed to improve water quality by controlling the amount of a pollutant entering a water body. (California State Water Resources Control Board:

 Toxicity – The degree to which a substance or mixture of substances can harm humans or animals. Acute toxicity involves harmful effects in an organism through a single or short-term exposure. Chronic toxicity is the ability of a substance or mixture of substances to cause harmful effects over an extended period, usually upon repeated or continuous exposure sometimes lasting for the entire life of the exposed organism. Subchronic toxicity is the ability of the substance to cause effects for more than one year but less than the lifetime of the exposed organism. (EPA:

 Turbidity – The amount of solid particles that are suspended in water and that cause light rays shining through the water to scatter. Thus, turbidity makes the water cloudy or even opaque in extreme cases. Turbidity is measured in nephelometric turbidity units (NTU) (USGS:

 Water Quality Objectives – Numerical or narrative limits on constituents or characteristics of water designed to protect designated beneficial uses of the water. California’s water quality objectives are established by the State and Regional Water Boards. (San Diego Basin Plan:

 Watershed – A watershed is the area of land where all of the water drains to the same place – this includes water that flows on the surface and water located underground. Watersheds come in all shapes and sizes. They cross county, state and national boundaries. (EPA:

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