Expert Query

Click on a program name to show or hide the views associated with it.
 303(d) Listing & TMDL Information
The National Total Maximum Daily Load (TMDL) Tracking System (NTTS) contains information on waters that are Not Supporting their designated uses. These waters are listed by the state as impaired under Section 303(d) of the Clean Water Act. The status of TMDLs are also tracked. TMDLs are pollution control measures that reduce the discharge of pollutants into impaired waters. For further information on TMDLs, please see Implementing Clean Water Act Section 303(d): Impaired Waters and Total Maximum Daily Loads (TMDLs).
 305(b) Water Assessments
The National Assessment Database (NAD) contains information on the attainment of water quality standards. Assessed waters are classified as either Fully Supporting, Threatened, or Not Supporting their designated uses. This information is reported in the National Water Quality Inventory Report to Congress under Section 305(b) of the Clean Water Act.
 Integrated Reporting Look-up Tables
In the Guidance for 2006 Assessment, Listing, and Reporting Requirements Pursuant to Sections 303(d), 305(b), and 314 of the Clean Water Act [2006 Integrated Report Guidance (IRG)], EPA provided information on the data elements that should be included in a States electronic data submission. EPA recommends that States use the Look-up Tables provided below when preparing their electronic data submission. This information is made available to the public via the Assessment and Total Maximum Daily Load (TMDL) Tracking and Implementation System (ATTAINS)..
 Statewide Statistical Surveys
Statewide statistical surveys are water quality assessments designed to yield unbiased estimates of the condition of a whole resource (such as all lakes or streams in a state) based on monitoring a representative sample of those waters. They can be used to track trends in water condition at the state scale or sub-state scale. Statistical surveys use standardized methods to quantify, with documented confidence, the extent of water quality problems and the extent of key stressors. Statistical surveys complement more traditional targeted monitoring and assessment programs that generally target only waters of concern or interest. For more information, see Assessing and Reporting Water Quality (Questions and Answers). Data from the 2012 Integrated Reporting cycle onward are available in the Expert Query views, and data from the 2010 Integrated Reporting cycle are only available in the ATTAINS web reports. To see which cycles are available for each state, please see the Status of Available Data report.
 Clean Watersheds Needs Survey (CWNS) Information for 2004
 Clean Watersheds Needs Survey (CWNS) Information for 2000
The Environmental Protection Agency's CWNS is required by Sections 205(a) and 516(b)(1) of the CWA. The CWNS is a summary of the estimated capital costs for water quality projects and other activities eligible for SRF support as authorized by the 1987 CWA Amendments. These activities include both facilities and certain water quality program elements. Activities include the planning, design, and construction of publicly owned wastewater collection and treatment systems and projects controlling CSOs, SW, and NPS pollutants. Other eligible water quality program elements are those that involve one-time expenditures supporting the CWA goals, such as program development and implementation. Ongoing expenditures, such as operation and maintenance (O&M) costs, are not included. For further information please click here.
Clean Water State Revolving Fund (CWSRF) Benefits Reporting
Clean Water State Revolving Fund program(CWSRF) provides capitalization grants to the states to be used as the basis(along with a required twenty percent state match), to create revolving loan funds which provide low-interest loans to municipalities to finance wastewater infrastructure projects, and to fund water quality projects such as nonpoint source and estuary management.
 Cross Program Information
These database views show the results of spatial queries that determine if a spatial overlap exists between entities of two different water programs. Like any spatial query, errors in determining the overlap can occur and they can be grouped as follows:
  • False Positives occur when the locational information of one the entities is either incorrect or not of sufficient quality to determine its exact location.
  • False Negatives occur when locational information is missing or not available for all of the entities.
In addition to the entity locational information, errors, although few, may also exist in the spatial network of rivers, streams, and other waterbodies that comprise the National Hydrography Database (NHD) jointly maintained by USGS and USEPA. Errors in the NHD may contribute both to false positive and false negative readings.