SB 547

This bill provides for a variance to limits on the amount of phosphorus allowed

in discharges to water bodies that contain excessive amounts of phosphorus, if

conditions specified in the bill are met. The bill also authorizes the use of adaptive

management, explained below, to comply with water quality standards for

phosphorus and total suspended solids.

Water quality standards and effluent limitations

The federal Clean Water Act allows the federal Environmental Protection

Agency (EPA) to delegate responsibilities under the act, including issuing

wastewater discharge permits for point sources (factories and sewage treatment

plants, for example), to a state if the state's laws comply with requirements in the

act. EPA has delegated these responsibilities to this state.

Consistent with the Clean Water Act, current state law requires the

Department of Natural Resources (DNR) to promulgate rules setting water quality

standards for the waters of the state. The standards include criteria for specific

pollutants. A criterion may be narrative (describing the characteristics that the

water should have) or numeric (specifying the maximum concentration of a

pollutant).

Under current federal and state law, wastewater discharge permits include

restrictions, called effluent limitations, on the amount of various pollutants that may

be discharged. One type of effluent limitation is applicable without regard to the

quality of the receiving water body and is based on the level of control achieved using

treatment technology that is reasonably available (considering cost, among other

things) for limiting the discharge of a pollutant. If this kind of limitation (called a

technology based effluent limitation) is not sufficient to ensure that a water quality

standard for a pollutant will be met in a particular water body, permits for sources

that discharge into the water body must generally contain effluent limitations for the

pollutant that are more stringent than the technology based effluent limitation and

that are designed to ensure that the water quality standard will be met. This kind

of limitation is called a water quality based effluent limitation.

Current law allows DNR to grant a permittee a variance to a water quality

based effluent limitation if the permittee demonstrates that complying with the

effluent limitation is not feasible for one of several reasons, including that applying

the effluent limitation to the source would cause substantial and widespread adverse

social and economic impacts in the area where the source is located. The term of a

variance may not exceed five years. A variance may be renewed, but only for as long

as it remains infeasible for the source to comply with the water quality based effluent

limitation. Variances are subject to review and approval by EPA.

Phosphorus water quality rules

In 2010, DNR promulgated rules adding a numerical water quality criterion to

the water quality standard for phosphorus. Some water bodies in Wisconsin do not