In December 2010, the Wisconsin Department of Natural Resources (WDNR) put into place new rules to control phosphorus discharges to the state’s waterways. In two prior client alerts, Wisconsin DNR’s New Phosphorus Rules: Are They in Effect? and Wisconsin DNR’s New Phosphorus Rules: They Are in Effect, we discussed the history and citizen suit notice of intent that led to the enactment of these rules, the basic framework of the rules, and the initial skirmish over whether the rules would go into effect as scheduled. They did. This third client alert is intended to bring that story forward in time.
Phosphorus Rules: Overview
The "phosphorus rules" are actually revisions to three existing rules which establish numerical criteria for phosphorus and implementation procedures for point sources, and performance standards for agriculture:
1. NR 102 Water Quality Standards for Wisconsin Surface Waters: the long-standing "narrative standard" has been replaced with numerical in-stream criteria for phosphorus:
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For 46 specifically identified rivers - 100 micrograms per liter (ug/L) also expressed as .1 milligrams per liter (mg/L)
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For all other streams, unless they are exempted - 75 ug/L (.075 mg/L)
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For lakes and reservoirs - from 15 ug/L (.015 mg/L) to 40 ug/L (.04 mg/L); the lower criterion applies to lakes that support a cold water fishery in the lower portions of the lake; the higher criterion applies to shallow lakes and reservoirs
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For the open and near shores of Lake Superior – 5 ug/L (.005 mg/L); for the open and near shore waters of Lake Michigan (with the exception of a limited segment near the mouth of the Fox River) – 7 ug/L (.007 mg/L)
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A criterion for a specific river segment or waterbody can be modified by adopting a site-specific rule.
2. NR 217 Effluent Standards and Limitations:
a. Adds water quality based effluent limitations (WQBELs) for phosphorus derived from the numerical criteria in NR 102 or a total maximum daily load (TMDL) for the specific waterbody, applicable to the following dischargers of phosphorus:
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Industrial
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Municipal
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Concentrated animal feeding operations (CAFOs) that discharge through a treatment system
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Municipal stormwater systems if necessary to meet phosphorus criteria
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Noncontact cooling water unless 100% of the phosphorus is from intake water
b. Establishes four compliance mechanisms (described more fully below):
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Traditional "bricks and mortar" treatment facility construction
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Variances
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Water quality trading
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Adaptive manageme
3. NR 151 Runoff Management: adds Phosphorus Index (P-Index) performance standards for agricultural sources to address runoff from agricultural lands:
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Applicable to croplands, pastures and winter grazing areas
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Requires a P-Index averaging 6 or less over the accounting period and less than 12 in any individual year
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Implemented through a nutrient management plan
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Became effective July 1, 2012
The balance of this Client Alert discusses the implementation tools and issues arising for point source dischargers.
Compliance Options: What are they?
Read more from: Linda H. Bochert of MICHAEL BEST & FRIEDRICH LLP
