State Development of Numeric Criteria for Nitrogen and Phosphorus Pollution

Map - N/P Criteria Progress

The map below shows a national summary of current numeric total nitrogen and total phosphorus EPA-approved criteria and those anticipated in the near future based on state-provided information. The information presented in the map is also presented as an interactive table under the Table - N/P Criteria Development tab.

Click the year of interest to see the relevant development status of N and P criteria. To see a detailed summary for a particular state, move your mouse cursor over (i.e., "mouseover") the desired state. For all the state's details, click on the state. Please note you can "zoom-in", "zoom-out", and "drag" the map to change how the map looks.

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States with Chlorophyll Criteria

The map below shows a national summary of current numeric EPA-approved chlorophyll-a criteria. While total nitrogen and total phosphorus criteria are preferable for directly determining TMDLs and NPDES permit discharge limits, states may still use chlorophyll-a criteria as a means for determining whether waters are impaired due to nitrogen and phosphorus pollution. Chlorophyll-a is a response variable that measures biotic productivity and activity, thus reflecting the nutrient enrichment of the system. Chlorophyll-a concentrations are a direct response to causal variables - total nitrogen and total phosphorus. See Technical Support for Numeric Nutrient Criteria Development.

To see a detailed summary for a particular state, move your mouse cursor over (i.e., "mouseover") the desired state. For all the state's details, click on the state. Please note you can "zoom-in", "zoom-out", and "drag" the map to change how the map looks.

Table - Criteria Progress

The table below shows a national summary of current EPA-approved numeric total nitrogen and total phosphorus criteria adoptions and those anticipated in the near future based on state-provided information. It also shows the status for related EPA-approved criteria such as chlorophyll-a. The information presented below is also presented as interactive maps under the Map - N/P Criteria Development and Map - Chlorophyll Criteria tabs.

Sort the table by clicking on any desired column. For example, you can sort by state, region, and expected level of progress. You can also show or hide columns by clicking on the checkboxes. For an explanation of the table symbols, click Table Legend or "mouseover" one of a states level cells (e.g., "Level 5). Click the state for complete detailed information.

Table Legend - Click to Show/Hide

Progress Levels

Nitrogen and Phosphorus Criteria

Level 5	Complete set of N and P criteria for all watertypes
Level 4	2 or more watertypes with N and/or P criteria
Level 3	1 watertype with N and/or P criteria
Level 2	Some waters with N and/or P criteria
Level 1	No N and/or P criteria

Chlorophyll-a Criteria

Level C5	Complete set of chlorophyll-a criteria for all watertypes
Level C4	2 or more watertypes with chlorophyll-a criteria
Level C3	1 watertype with chlorophyll-a criteria
Level C2	Some waters with chlorophyll-a criteria
Level C1	No chlorophyll-a criteria

Criteria Balls

Criteria balls represent each state's status regarding adopted or planned N and P criteria for three major watertypes. They're also used to represent status for chlorophyll-a criteria Three criteria balls are always displayed left-to-right in the following order:

1. Lakes/Reservoirs
2. Rivers/Streams
3. Estuaries

Each N/P criteria ball has two halves - the left half represents TN criteria status while the right represents TP. The table uses a "watertype not applicable" ball if a state does not have one or more of the three watertypes.

Chlorophyll-a criteria balls are similar to the N/P ones. However, these are not halved.

N	P	Chl-a
			Statewide criteria
			Partial criteria (Categorical criteria, site-specific criteria, etc.)
			No criteria
			Watertype Not Applicable

Note: The fully-shaded halves of each N/P criteria ball correspond to one point under the WQ-1a performance measure described under the Strategic Plan tab.

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Click to Show/Hide Table Columns

N/P Progress							Chlor-a	Related Parameters	Number of Categories or Sites with Criteria
1998	2008	2013	2014	Current	2015	2016			Lakes/Reservoirs	Rivers/Streams	Estuaries

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Table Legend - Click to Show/Hide

Progress Levels

Nitrogen and Phosphorus Criteria

Level 5	Complete set of N and P criteria for all watertypes
Level 4	2 or more watertypes with N and/or P criteria
Level 3	1 watertype with N and/or P criteria
Level 2	Some waters with N and/or P criteria
Level 1	No N and/or P criteria

Chlorophyll-a Criteria

Level C5	Complete set of chlorophyll-a criteria for all watertypes
Level C4	2 or more watertypes with chlorophyll-a criteria
Level C3	1 watertype with chlorophyll-a criteria
Level C2	Some waters with chlorophyll-a criteria
Level C1	No chlorophyll-a criteria

Criteria Balls

Criteria balls represent each state's status regarding adopted or planned N and P criteria for three major watertypes. They're also used to represent status for chlorophyll-a criteria Three criteria balls are always displayed left-to-right in the following order:

1. Lakes/Reservoirs
2. Rivers/Streams
3. Estuaries

Each N/P criteria ball has two halves - the left half represents TN criteria status while the right represents TP. The table uses a "watertype not applicable" ball if a state does not have one or more of the three watertypes.

Chlorophyll-a criteria balls are similar to the N/P ones. However, these are not halved.

N	P	Chl-a
			Statewide criteria
			Partial criteria (Categorical criteria, site-specific criteria, etc.)
			No criteria
			Watertype Not Applicable

Note: The fully-shaded halves of each N/P criteria ball correspond to one point under the WQ-1a performance measure described under the Strategic Plan tab.

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State Milestones

1. Planning for Criteria Development,
2. Collection of Information and Data,
3. Analysis of Information and Data,
4. Proposal of Criteria, and
5. Adoption of Criteria (EPA-approved).

Sort the table by clicking on any desired column. For example, you can sort by state, region, and expected watertype. You can also show or hide columns by clicking on the checkboxes. Click the state for complete detailed information.

Strategic Plan - Performance Measures for N/P Criteria Development

For FY 2015, there are two measures that set performance goals and track progress toward developing statewide criteria for total nitrogen and phosphorus - WQ-1a and WQ-26.

WQ-1a: Number of numeric water quality standards for total nitrogen and for total phosphorus adopted by States and Territories and approved by EPA, or promulgated by EPA, for all waters within the State or Territory for each of the following waterbody types: lakes/reservoirs, rivers/streams, and estuaries.

WQ-26: Number of states and territories implementing nutrient reduction strategies by (1) setting priorities on a watershed or state-wide basis, (2) establishing nutrient reduction targets, and (3) continuing to make progress (and provide performance milestone information to EPA) on adoption of numeric nutrient criteria for at least one class of waters by no later than 2016. (cumulative)

For complete details and definitions describing the above performance measures, see FY 2015 NWPG Water Quality Measure Definitions

The table below compares credit under WQ-1a by year. Credit under part 3 of WQ-26 (WQ-26:pt3) is also presented. Sort the table by clicking on any desired column. For example, you can sort by state, region, and expected level of progress.

• Past and current WQ-1a credit is based on what the state or territory has actually accomplished based on the measure definition.
• Future WQ-1a credit is based on milestone information provided by the state.
• Maximum credit for WQ-1a varies from 2 to 6 criteria depending on whether the state has the applicable water types.
• Credit for part 3 of WQ-26 (WQ-26:pt3) is based upon whether a state has either completed - or has demonstrated they will complete by 2016 - statewide numeric nutrient criteria for one or more classes of waters defined by the measure (i.e., lakes/reservoirs, rivers/streams, or estuaries).
• Maximum credit for WQ-26:pt3 is 0.33 even if a state has complete TN/TP criteria for more than 1 watertype.
• Fiscal Years apply to performance measures and indicate progress anticipated for that year. A particular fiscal year begins on October 1st of the previous calendar year and ends the following September 30th. (For example, FY 2013 begins October 1, 2012 and ends September 30, 2013.)

State & Territorial Details

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