Wisconsin Administrative Code › Department of Natural Resources › NR 100-199 - Environmental Protection - General › Chapter NR 106 - Procedures For Calculating Water Quality Based Effluent Limitations For Point Source Discharges To Surface Waters › Subchapter V - Effluent Limitations for Temperature › Section NR 106.55 - Determination of water quality-based effluent limitations for temperature in WPDES permits

Current through June 24, 2024
(1) GENERAL. The department shall determine
				  water quality-based effluent limitations for temperature to attain and maintain
				  water quality standards and criteria specified in or determined according to
				  procedures in subch. II of ch. NR 102.
(2) LIMITATIONS FOR WATERS DESIGNATED AS
				  LIMITED AQUATIC LIFE. The daily maximum effluent temperature limitation shall
				  be 86°F for discharges to surface waters classified as limited aquatic life
				  according to s.
				  NR
				  104.02(3) (b) 1. and as defined in s.
				  NR
				  104.02(1), except for those
				  classified as wastewater effluent channels and for wetlands regulated under ch.
				  NR 103.
(3) LIMITATIONS FOR WATERS
				  DESIGNATED AS WASTEWATER EFFLUENT CHANNELS. The daily maximum effluent
				  temperature limitation shall be 120°F for discharges to surface waters
				  classified as limited aquatic life wastewater effluent channels according to s.
				  NR
				  104.02(3) (b) 1. and as defined in s.
				  NR
				  104.02(1) (d).
(4) LIMITATIONS FOR WETLANDS. Effluent
				  temperature limitations shall be established for wetlands on a case-by-case
				  basis to meet the water quality standards provided in ch. NR 103, but in no
				  case shall the effluent temperature limitation be greater than
				  120°F.
(5) LIMITATIONS FOR
				  DISCHARGES TO STORM SEWERS.
(a)
General.
A permittee may request, at time of permit
				  application, an effluent limitation greater than the effluent temperature
				  limitations required under subs. (2) to (4), (6) or (7) if the discharge is to
				  a storm sewer or other storm water conveyance channel. The permittee may
				  request that the higher effluent limitation be greater than 120°F if the
				  permittee is able to demonstrate to the satisfaction of the department that the
				  heated effluent is not discharged in a manner that will cause a potential for
				  scalding of humans. An effluent temperature limitation established under this
				  subsection shall be determined according to the following equation:
Tss = Tdir +
					 (HLV x (L/100))
Where:
Tss = Effluent temperature
					 limitation for discharge to a storm sewer in degrees Fahrenheit
					 dir
T = Effluent temperature limitation determined under sub.
					 (2), (3), (4), (6) or (7) in degrees Fahrenheit
HLV = Heat loss value assumed to be 0.25 unless an
					 alternative value is determined to be representative of site-specific
					 conditions
L = Length (in feet) of the storm sewer or other storm
					 water conveyance channel between the effluent discharge location and the point
					 at which the storm sewer or storm water conveyance channel discharges to a
					 surface water of the state.
(b)
Alternative heat loss
				  value.
An alternative heat loss value (HLV) may be used in the
				  equation in par. (a). The alternative value shall be representative of seasonal
				  influences on heat loss and be based on a comparison of effluent temperature at
				  the location of discharge to the storm sewer or storm water conveyance channel
				  and the point at which the storm sewer or storm water conveyance channel
				  discharges to a surface water of the state.
(c)
Site-specific
				  information.
The department may use available site-specific
				  information to determine an alternative heat loss value or other data
				  demonstrating the amount of heat loss in a storm sewer to establish an effluent
				  temperature limitation for discharges to a storm sewer.