California Water Boards' Annual Performance Report - Fiscal Year  2019-20 

Water Quality Report Cards

See the regional Water Quality Control Board Offices below.

Region 1 - North Coast Region 2 - San Francisco Bay Region 3 - Central Coast
Region 4 - Los Angeles Region 5 - Central Valley Region 6 - Lahontan
Region 7 - Colorado River Region 8 - Santa Ana Region 9 - San Diego


  • Data Source: California Total Maximum Daily Load (TMDL) Program Status Summary Report Fiscal Year  19-20
  • Data Definitions: TMDL Project: A TMDL project is a planned strategy to reduce pollution in an impaired waterbody so that its water quality standards are met. A TMDL project may address more than one or more waterbody-pollutant combinations for a given waterbody or segment of waterbody (known as 303(d) listings). A TMDL project includes the development of the TMDL, and TMDL implementation plan, or a USEPA approved alternatives to TMDLs, category 4b projects. A TMDL is comprised of a calculation of the maximum amount of a pollutant that the waterbody can receive and still meet water quality standards (i.e., waterbody's assimilative capacity); an allocation of acceptable pollutant loading to the various sources of the pollutant; and in California, an implementation plan for restoring water quality. A category 4b project is an alternative approach that implements pollution control requirements (e.g., best management practices) that is stringent enough to implement applicable water quality standards within a reasonable period of time. 303(d) Listing: A 303(d) listings is a waterbody-pollutant combination that is responsible for the impairment as specified on the Water Boards' Clean Water Act Section 303(d) List of Impaired Waterbodies (i.e., each waterbody-pollutant combination is called a listing). If a single waterbody is impaired by multiple pollutants, the waterbody will have multiple listings, one for each pollutant. The geographic extent of a listing may vary from a small segment of a stream to an entire watershed. The current TMDL projects and listings are documented in the Water Boards' 2010 Clean Water Act Section 303(d) List of Impaired Waterbodies.
  • References:


Map of California with regional board boundries


Attainment Date
The projected year water quality targets will be achieved. The attainment date is estimated based on available information at the time of the most recent update to the water quality restoration plan. The attainment date is subject to change.

Beneficial Uses
Beneficial uses define the uses of water. The California Water Code defines beneficial uses of the waters of the state as uses that may be protected against quality degradation include, but are not limited to: domestic, municipal, agricultural and industrial supply; power generation; recreation; aesthetic enjoyment; navigation; and preservation and enhancement of fish, wildlife, and other aquatic resources or preserves.

Effective Date
The date upon which the TMDL or other implementation action (e.g., Cleanup and Abatement Order) is considered to take effect.

Implementation Outcome Status Assessed
A water quality report card has been prepared showing the outcome of implementing water quality restoration plans (TMDLs or other approach) that have already been adopted. It is important to note that Regional Boards may be implementing water quality restoration plans (e.g., incorporating TMDL requirements into permits, reviewing water quality data, etc.) for projects for which a Water Quality Improvement Report Card has not yet been created.

A pollutant is a waste or substance that, at certain levels, can cause waterbody impairment. The monitoring programs of the Water Boards and others provide information on the levels of pollutants in the State's waters.

Pollutant Types
Point Source Pollutant
Pollutants that are, or may be, discharged from any discernible, confined, and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft.

Nonpoint Source (NPS) Pollutant
Pollutants that are or may be discharged from diffuse sources without a single identifiable point of origin. These discharges include, but are not limited to, runoff from agriculture, forestry, grazing, hydromodification, wetlands, and marinas and recreational boating activities.

Legacy Pollutant
Pollutants that are primarily the result of historical contributions. They result from activities such as agricultural, manufacturing, and mining activities no longer practiced and include some pollutants currently banned by regulation. These pollutants have the common characteristic of persistence in the environment and may have an affinity for sediments. Typically, the decline in environmental legacy pollutant concentrations occurs as a result of natural attenuation processes.

Water Quality Objective
The limit or level of water quality constituents or characteristics which are established for the reasonable protection of beneficial uses of water or the prevention of nuisance within a specific area.

Water Quality Target
The water quality target is a description of the desired condition in the watershed or waterbody. Typically, targets are tied to specific water quality standards that provide measurable goals for the water quality restoration plan.


Conditions Improving
Water quality data and/or other indicators demonstrate improvement; BUT
The final water quality targets not consistently being met.
Data Inconclusive
Not enough data (of acceptable quality) has been collected to demonstrate that the water quality targets are consistently met; OR
Variability in data do not permit a determination in water quality trends (positive or negative).
Improvement Needed
Final water quality targets not consistently met; AND
In Water Board staff judgment, water quality data and/or other indicators demonstrate that water quality is either declining or not improving.
Targets Achieved/ Waterbody Delisted
Water quality data or other information demonstrate that final water quality targets are consistently met; OR
The waterbody has been removed from the 303(d) list.