Data Solicitation

data solicitation period

The Integrated Report satisfies two of the state’s reporting requirements under the Clean Water Act ("CWA"). One is the CWA section 305(b) requirement to report on water quality conditions (commonly called the “305(b) report”). The other is the CWA section 303(d) requirement to identify impaired waterbodies that are not meeting or not expected to meet water quality standards (commonly called the “303(d) list of impaired waters” or the “303(d) list”). The 303(d) list also includes a schedule for waters on the list for which a total maximum daily load or other water quality restoration project will be established in the future.

The 303(d) list is prepared in accordance with the Water Quality Control Policy for Developing California’s Clean Water Act Section 303(d) List (“Listing Policy”).  

Each Integrated Report Cycle begins with a public Notice of Data Solicitation (“Notice”) distributed by the State Water Resources Control Board (“State Water Board”).  The Notice identifies the upcoming cycle, lists the Regional Water Quality Control Boards (“Regional Water Boards”) that are “on-cycle,” describes the procedures and requirements for submitting data and information, and establishes a cut-off date by which all data should be submitted for consideration during the cycle.  Each Integrated Report will include information primarily from the “on-cycle” regions but can include information from “off-cycle” regions.  (Please visit the All Integrated Report Cycles page for more information about the Integrated Report Cycles.)

“Readily available data and information” submitted during data solicitation will be assembled (e.g., gathered and organized), evaluated to consider whether or how data and information will be used and, if appropriate, assessed to determine surface water quality conditions and to identify impaired waters. Readily available data and information is defined as data and information successfully submitted to the State Water Board via the California Environmental Data Exchange Network ("CEDEN"), except as otherwise noted in the Notice, by the cut-off date.

General instructions for submitting data and information for the Integrated Report are provided below. To be considered for the 303(d) list, data and information submissions must include the minimum data elements required for assessment and be received by the deadline identified in the Notice. See Data and Information Submittal Requirements  for the minimum data elements and instructions for submitting data and information. The State Water Board may also consider such data and information in the development of the 305(b) report.

The State Water Board and Regional Water Quality Control Boards (collectively the “Water Boards”) encourage continuous submittal of data and information for any surface waterbody in California because the Water Boards may conduct listing or delisting assessments using data and information at its discretion. 



Data and Information Submittal Basics


What is the overall data and information submittal process?

The figure below illustrates the process for submitting data and information for the Integrated Report. Data that can be accepted by the California Environmental Data Exchange Network ("CEDEN") must be submitted to CEDEN. Data and information that are not CEDEN compatible can be submitted via the Integrated Report Upload Portal.

In addition, a Quality Assurance Project Plan ("QAPP") or QAPP equivalent documentation per Section 6.1.4 of the Listing Policy must accompany any data submitted to either CEDEN or the Integrated Report Upload Portal to be utilized for the 303(d) list. Data and information not accompanied by a QAPP or a QAPP equivalent documentation cannot be used by itself to support a 303(d) listing or delisting decision. QAPPs or equivalent documents can be submitted via the Integrated Report Upload Portal.

CEDEN does not store QAPP documents and the QAPP information in CEDEN is insufficient to determine if data are useable for assessments.

How is “readily available data and information” defined?

The Listing Policy defines “readily available data and information” as data and information that can be submitted to [CEDEN] as directed in the notice of solicitation. If CEDEN is unable to accept a particular subset of data and information, the State Water Board or the Regional Water Board will accept that data and information if it meets the formatting and quality assurance requirements detailed in section 6.1.4 of the [Listing] Policy and the notice of solicitation for the current listing cycle” (Listing Policy, Section 6.1.1.).

“Information” is considered to mean any documentation, such as narrative or photographic evidence, describing the water quality condition of a surface water body.

“Data” are considered to mean a subset of information that consist of reports detailing measurements of specific environmental characteristics (i.e., measurements of physical, chemical, or biological characteristics in aquatic environments).

What are CEDEN compatible data?

CEDEN compatible data sets include water chemistry, sediment chemistry, toxicity, tissue and bioassessment data, along with associated geospatial information (e.g., latitude, longitude of sampling locations). CEDEN compatible data must be submitted through CEDEN.

CEDEN accepts the following data types:

  • Chemistry:  laboratory results from water samples or sediment samples
  • Field collection:  measurements collected in the field, including data from field probes and habitat surveys
  • Toxicity:  laboratory results from water column or sediment toxicity tests
  • Tissue:  laboratory results from fish tissue or other tissue samples
  • Bioassessment:  habitat measures and observations, and measurements of biology such as benthic macroinvertebrate and algae taxonomy

For instructions on submitting data to CEDEN, see Data and Information Submittal Requirements. The CEDEN website is found here: http://ceden.org/303d_list.shtml.

For instructions on submitting a QAPP or QAPP equivalent documentation for CEDEN compatible data, see Data and Information Submittal Requirements.

What are Non-CEDEN compatible data and information?

Data and information that are not CEDEN compatible include continuous monitoring data (e.g., data collected by an in-situ sonde) and narrative or photographic evidence. For instructions on submitting non-CEDEN compatible data, see the Data and Information Submittal Requirements.

For instructions on submitting a QAPP or QAPP equivalent documentation for non-CEDEN data, see the Data and Information Submittal Requirements .

When should data and information be submitted?

Data and information can be uploaded to CEDEN or the Integrated Report Upload Portal at any time. The State Water Board recommends data and information be submitted early to reduce and to avoid backlogs in data and information uploading. However, data and information must be submitted by noon on October 21, 2022, to be evaluated for the 2026 Integrated Report. Data and information submitted after noon on October 21, 2022, will be evaluated in future Integrated Reports.

Who can submit data and information?

Any person or entity (including but not limited to private citizens; local, state, and federal governmental agencies; non-profit organizations; and businesses) possessing information regarding the quality of California’s waters may submit data and information.

Which waterbodies are the focus of the 2026 listing cycle?

The listing cycle for the 2026 Integrated Report focuses on surface waterbodies such as rivers, streams, lakes, reservoirs, estuaries, lagoons, bays, and ocean waters in the following areas of California:

  • The regions of the North Coast, Lahontan, and Colorado River Basin Regional Water Boards.
  • The San Joaquin River sub-area of the Central Valley Regional Water Board, which is defined as the San Joaquin River watershed and includes the mainstem of the San Joaquin River upstream of the legal boundary of the Sacramento-San Joaquin Delta and all surface waters tributary to the mainstem.  

If data and information submitted during the 2026 data solicitation period for a waterbody that’s considered “off-cycle” and not used in the 2026 Integrated Report, that data and information will be evaluated no later than the next time that waterbody is “on-cycle”. However, the Water Boards encourage continuous submittal of data and information for any surface waterbody in California because the Water Boards may conduct listing or delisting assessments using data and information at its discretion.

What kind of data and information should be submitted?

Any data and information that contribute to a more complete understanding of the quality of the state’s surface waters should be submitted. This includes data and information that will help the Water Boards’ staff determine if water quality standards are being attained or not attained. Any data and information not submitted for a previous Integrated Report cycle should be submitted. This includes data and information collected since the end of the 2024 cycle solicitation period (October 16, 2020) as well as data and information collected prior to that date but not submitted.

The 2026 Integrated Report is expected to use both quantitative and qualitative information. The bulk of the data used in the 2026 Integrated Report is expected to be quantitative, or numeric. These data provide the basis to develop primary lines of evidence ("LOEs"). Qualitative information consists of non-numeric evidence such as photographs or narrative data. Qualitative information is used to develop ancillary LOEs, in some cases. For greater detail on how different data types are used, see Section 3 of the Listing Policy.

Data and information submitted may pertain to individual waterbody segments, entire waterbodies, or whole watersheds in California.

What kind of data should not be submitted?

Please do not submit:

  • Data and information previously submitted as part of a past Integrated Report listing cycle
  • Data already submitted into CEDEN
  • Data and information pertaining to groundwater
  • Data and information from collection locations deemed not representative of ambient conditions in the waterbody segment (e.g., storm drain outfalls, effluent discharge)
  • Data submitted directly to the U.S. EPA via the Water Quality Exchange (“WQX”)

What if I have already submitted data to federal systems like the Water Quality Exchange data system?

The Water Boards recognize that federal, agencies, tribal, and other entities submit data directly to the U.S. EPA via the Water Quality Exchange ("WQX") and it is not feasible to require that those datasets also be uploaded into CEDEN.

Consequently, the Water Boards' staff will pull data directly from the Water Quality Portal which connects to the WQX and attempt to translate that data into a CEDEN compatible format for use in the Integrated Report process. Datasets will only be used for the 2026 Integrated Report if they conform to the minimum data elements and quality requirements as described in the Data and Information Submittal Requirements.

How will the data and information be evaluated for use?

After the end of the solicitation period (October 21, 2022) all data and information submitted will be assembled and evaluated for the minimum data elements, including quality requirements. 

QAPPs submitted for the data will be reviewed by the Water Boards’ staff. Per section 6.1.4 of the Listing Policy: If the data collection and analysis is not supported by a QAPP (or equivalent) or if it is not possible to tell if the data collection and analysis were supported by a QAPP (or equivalent), then the data and information should not be used by itself to support listing or delisting of a water segment. All data of whatever quality can be used as part of a weight of evidence determination (sections 3.11 or 4.11).

Data will be screened for quality using an automated data quality estimator tool and reviewed by the Water Boards’ staff. Data identified by the screening tool as inaccurate or of low quality may not be used as primary lines of evidence for assessment. Instances where data may not be used as primary lines of evidence include, but are not limited to:

  • QAPP or QAPP equivalent documentation not provided or that does not meet the requirements outlined in the Data Submittal and Information Requirements 
  • Data with inaccurate or missing spatial information (e.g., latitude and longitude)
  • Data that are not temporally or spatially representative of the waterbody 
  • Data that are not appropriate for assessment of ambient surface water quality (e.g., effluent, groundwater, air samples)
  • Rejected data or data of poor quality (e.g., holding time violations, failed quality control checks) 
  • Data that are quality control measurements and not appropriate for assessment (e.g., laboratory duplicates, blanks from control samples, matrix spikes, surrogate measurements)
  • Data where the sample value is less than the quantitation limit and the quantitation limit is greater than the water quality standard, objective, criterion, or evaluation guideline

The data of sufficient quality will be compared to water quality standards. Water quality standards include beneficial uses of water and water quality objectives or criteria as listed in the Regional Water Boards’ water quality control plans (known as “basin plans”), statewide water quality control plans (e.g., the California Ocean Plan), the California Toxics Rule at 65 Federal Reg. 31681, and pertinent state and federal laws and regulations. Basin plan amendments that incorporate revised water quality objectives after the data solicitation cutoff date may not be used in the 2026 listing cycle but will be incorporated in future listing cycles.