Integrated Water Quality Monitoring and Assessment Reporting

Rhode Island's Section 305(b) State of the State's Waters Report and Section 303(d) List of Impaired Waters

Background

The federal Clean Water Act under Section 305(b) requires states to assess and report on the overall quality of waters in their state. Section 303(d) of the federal Clean Water Act requires each state to identify waters for which existing required pollution controls are not stringent enough to achieve the State's water quality standards. These waters are referred to as "water quality limited" or "impaired". The federal Clean Water Act requires the assessment and identification of impaired waters to be conducted by states biennially.

Every even year, all readily accessible water quality data and information is evaluated by RIDEM Office of Water Resources. The methodology for this assessment process is outlined in Rhode Island's Consolidated Assessment and Listing Methodology (CALM). The use support status is determined by comparing readily available water quality data and information that meet data quality assurances and objectives to the water quality standards established in the Rhode Island Water Quality Regulations

The results of this comparison are then used to assess each waterbody's specific designated uses as "Fully Supporting" or "Not Supporting". If data is not available to evaluate a designated use, it is considered "Not Assessed". Each waterbody is assigned several designated uses, based on their classification in the  Rhode Island Water Quality Regulations. All waterbodies are assigned and assessed for recreational, aquatic life, and fish consumption designated uses, while subsets of waters are also assigned and assessed for drinking water and shellfishing designated uses.

Waterbodies that are not meeting their criteria or designated uses are placed on the state's List of Impaired Waters which is developed in accordance with Section 303(d) of the federal Clean Water Act. This List is prioritized and schedules are set for developing Water Quality Restoration Plans, also known as Total Maximum Daily Loads (TMDLs).

Integrated Report

Prior to 2008, DEM submitted the 305(b) Report and 303(d) List as separate documents. After 2008, USEPA guidance recommends that states develop and submit a single Integrated Water Quality Monitoring and Assessment Report (Integrated Report) document combining the 305(b) and 303(d) information. The Integrated Report format is intended to provide a streamlined approach to assessing and reporting on water quality. The Integrated Report format provides an Integrated List consisting of 5 categories of water quality assessment information, including the 303(d) Impaired Waters List.

Assessment of each designated use may result in different use support attainment status for each designated uses of an individual waterbody. For example, a waterbody may be Fully Supporting swimming use, but there may be insufficient data to develop an aquatic life use support status. Once all designated uses are assessed, each waterbody is placed into only one of the five reporting categories based on a hierarchical approach. Any waters with one or more designated uses being identified as "water quality limited" or "impaired" will be placed on the Impaired Water List, even if some designated uses are meeting water quality standards. 

The Integrated List is generated by placing each surface waterbody of the state into one of the following five hierarchical assessment categories, with Category 4 having 3 sub-categories:

Category                        Integrated Report Description Meaning

1

 

Attaining all designated uses

No use is threatened

Considered "fully supporting" all designated uses

2

 

Attaining some designated uses

No use is threatened

Insufficient or no data is available to assess other designated uses

Some designated uses are "fully supporting", more data is needed for other designated uses

3

  Insufficient or no data is available to assess any of the designated uses More monitoring data is needed

4

  Impaired or threatened for 1 or more designated uses but does not required a TMDL plan, because: Impaired of threatened but no TMDL plan development is needed

 

A TMDL has already been completed Waterbodies will be placed in this subcategory once all TMDLs for the waterbody have been developed and approved by USEPA.

 

B Other pollution control measures are reasonably expected to result in attainment in near future  

 

C Impairment is not caused by a pollutant (e.g. aquatic invasive species, flow)  

5

  Impaired of threatened for 1 or more designated uses and requires a TMDL plan

Development of TMDL plan needed

303(d) Impaired Waters List