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Preparing for Converting to ADB v.2

This page contains information intended to make the transition to ADBv.2 for the next cycle as smooth as possible. The following items will provide a general description of the ADB and how it relates to the 2008 Integrated Reporting Guidance. For more information about the new data elements required by the new guidance visit

  • Documentation
  • Data Elements Required for V.2
  • GIS Coverages
  • More information about ADB v.2

      You can learn more about the features of ADB v.2 by clicking on Features in ADB v.2


      The new Guidance requests that States provide two documents, one that describes the State's Monitoring Strategy and one that details that State's Assessment Methodology. It is a good idea to go ahead and prepare these documents. It is also recommended that you document your assumptions or your use of the existing codes when preparing assessment data elements. Your State's Assessment Methodology document is a good place to do this.

      Data Elements that are required for v.2

    • Assessment Unit ID
    • Assessment Unit Name
    • Assessment Unit Location
    • Water Type
    • Water size
    • Assessment Types

      The ADB v.2 uses a collection of cause and source codes. These codes are designed to be compatible with other EPA database systems like STORET and PCS. To View a complete list of the new Cause and Source codes visit Additionally, the ADB v.2 requires linkages between uses and causes and causes and sources to track the relationships between sources, causes and overall water quality.

      The message for potential ADB users is use specific cause and source codes whenever possible. The ADB v.2 will not allow you to use general causes, like "Metals", so make sure you use specific causes like "Mercury". This same message holds true for sources. There is no code for "Agriculture" in the ADB v.2, so you will need to be more specific and use codes like "Confined Animal Feeding Operations".

      Designated Uses

      ADB v.2 uses State Designated Uses that are entered in EPA's WQSDB. You can access the WQSDB at to see the designated uses in the WQSDB for your state. Since the WQSDB will not be updated in the future any changes in uses from what is currently in the database must be supported by the state's WQS document and be approved by your EPA region.

        If you are using the designated use categories that correspond to uses in the WQSDB, you should document how these uses translate to the State designated uses described in the State's Water Quality Standards document. This will allow your data to be ported correctly into the ADB v.2. For example, if you are using the Fish Consumption designated use as a surrogate for Cold Water Aquatic Life Use, document that. Or, if there is not a specific Fish Consumption Use specified in your standards, but it's included in another standard, like Recreation or Aquatic Life Use, document that.

        There is no Overall Use in ADB v.2. If you are using Overall Use and it represents designated uses in your standards, make sure you document it. Otherwise, it will be lost during the porting process.

        Another designation worth mentioning is Antidegradation waters. Unless this is explicitly defined as a use in your State water quality standards, you will not be able to assign it as a Designated Use in ADB v.2. If you wish to store information about antidegradation waters or special resource waters that are not designated by the WQSDB, you will need to create a separate table.

        Use Support

        The Use Support categories in ADB v.2 are

      • Fully Supporting
      • Insufficient Information
      • Not Supporting
      • Not Assessed
          If your State has been using "Threatened", "Partially Supporting", and "Not Attainable", then you need to document how these use support categories should be reassigned in ADB v.2. By default, "Partially Supporting" waters will become "Not Supporting" and "Not Attainable" will become "Not Assessed".

          "Threatened" is no longer a use support category, but any use can be marked as threatened. For example, a use can be "Fully Supporting" and "Threatened". Waters with a "Threatened" use in ADB v.2 are treated the same as waters not supporting a use for category assignment. Also, you can mark waters with a "Partially Supporting" flag for your internal reference. However, in the ADB v.2, the "Partial" flag will have no effect on the category listing.

          GIS Coverages

          The new Guidance encourages States to create GIS coverages using the National Hydrography Dataset in order to describe the location of their waterbody segments/assessment units. EPA provides the NHD Reach Indexing Tool (NHD-RIT) to assist with this process. One advantage of using this methodology is that there is an ADB-RIT extension for ADB v.2 that assists users in using their NHD-based GIS coverages to calculate waterbody segment/assessment unit size for use in the ADB. Visit the Using GIS with ADB v.2 section to find out more about the ADBv2-RIT.

          Also, under the new Guidance, States are expected to account for all of the waters in the State, even those that are unassessed. The ADBv2-RIT will also provide tools for helping States delineate and determine size estimates for these unassessed waters. For more information about the NHD-RIT visit

          If you choose not to use NHD and the GIS tools provided by EPA, but still wish to submit a GIS coverage, be sure that your coverage includes sufficient metadata so that it can be used appropriately by EPA. At a minimum this metadata should include the projection information for the coverage. You can find more detailed metadata guidelines at EPA Disclaimer.

          More Information About the ADBv.2

          The Guidance refers to assigning the States’ waters to categories based on use support and the types of causes. The assignment of waters to categories is automatic in ADB v.2, so you do not need to worry about assigning waters to categories if you are planning to use the new system. For more information on how categories are assigned to waters in ADB v.2 (by overall assessment unit or by designated use), visit

          Please see the Reference section for the ADB User Guide where you can get more detailed information about features in the ADB v.2.

          If you have questions about the new ADB v.2, contact Dwane Young at EPA's Office of Water Monitoring Branch at

        • Features in
          Version 2


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