Section 102.26. Site-specific ambient temperatures.

 

(1)   Development of site-specific ambient temperatures . An owner or operator of a facility with a discharge subject to regulation under this chapter may submit a request to the department for the determination of a site-specific ambient temperature. The department may approve, disapprove or approve with modifications the request for the site-specific ambient temperature. The request for site-specific ambient temperatures shall include all of the following:

(a) A demonstration that the data used to derive the ambient temperatures in s. NR 102.25 do not apply to the specific water segment or body in question.

(b) Site-specific water temperature that represents the ambient temperature of the site. For purposes of this paragraph, data must be:

1. Collected daily using a continuous recorder or similar device that takes measurements at least hourly, except as follows:

a. Monthly data sets may be missing no more than 10 days of temperature data for the months of December through February,

b. Monthly data sets may be missing no more than 5 days of temperature data for the months of March through November.

2. Collected for each month in which the request for site-specific ambient temperatures is requested,

3. Collected at any time since October 1987,

4. Collected for at least 2 consecutive years.

(c) Calculated daily average temperatures from the data from par. (b) .

(d) Calculated monthly average temperatures from the daily average temperatures in par. (c) for each individual month that data has been collected. Alternatively, calculated monthly average temperatures directly from the data from par. (b) for each individual month.

(e) All individual monthly averages organized by month.

(f) A determination of the monthly site-specific ambient temperatures by calculating the geometric mean of all monthly averages for each given month.

(g) Alternative methods for developing site-specific ambient temperatures, if the department approves the method as representative of ambient temperatures as those in pars. (a) to (d) .

(2)   Use of site-specific ambient temperatures to establish acute criteria . Once site-specific ambient temperatures have been approved by the department in accordance with sub. (1) , the acute water quality criteria listed in Table 6 will be applicable for the protection of fish and other aquatic life.

(3)   Use of site-specific ambient temperatures to establish sub-lethal criteria . Once site-specific ambient temperatures have been approved by the department in accordance with sub. (1) , the sub-lethal water quality criteria applicable for the protection of fish and other aquatic life shall be calculated as follows:

(a) Use Table 7 to determine the appropriate sub-lethal criteria for the fish and other aquatic life use.

(b) Modify the sub-lethal criteria as follows:

1. If a sub-lethal criterion from par. (a) is less than the site-specific ambient temperature from sub. (1) for a given month, increase the sub-lethal criterion to be equal with the site-specific ambient temperature.

2. If a sub-lethal criterion from par. (a) is greater than an acute criterion for a given month from sub. (2) decrease the sub-lethal criterion to be equal with the acute criterion.

(c) Perform a fifth order polynomial regression of the 12 monthly sub-lethal criteria resulting from par. (b) . Using the resulting equation of the regression, calculate the final sub-lethal criteria for each month by replacing the "x" variables in the equation with a numeric representation for each month, where January "x" = 1, for February "x" = 2, … and for December "x" = 12.

(d) The final sub-lethal criteria from par. (c) shall be used in combination with the site-specific ambient temperatures developed in sub. (1) and the acute criteria determined in sub. (2) .

Table 6

Acute Criteria Across All Ambient Temperatures

(All values are expressed as degrees Fahrenheit) - See PDF for table

1 Ta = ambient temperature

2 Cold = waters with a fish and other aquatic life use designation of "cold water community"

3 Warm = waters with a fish and other aquatic life use designation of "warm water sport fish community" or "warm water forage fish community"

4 LFF = waters with a designation of "limited forage fish community"

5 N Lake = applicable for those lakes north of State Highway 10

6 S Lake = applicable for those lakes south of State Highway 10

7 SGB = Green Bay waters south of the Brown County line to the Fox River mouth

8 NGB = Green Bay waters north of the Brown County line to the northernmost point on Washington Island

9 NLKMI = Lake Michigan waters north of the Milwaukee River mouth (downtown Milwaukee)

10 SLKMI = Lake Michigan waters south of the Milwaukee River mouth (downtown Milwaukee)

11 LKSUP = waters in Lake Superior except those in Chequamegon Bay

12 CB = Chequamegon Bay waters within the region enclosed by Chequamegon Point and a straight line west to the mainland

Table 7

Raw Monthly Sub-Lethal Criteria for Use In Determining Final Sub-Lethal Criteria
with Site-Specific Ambient Temperatures

(All values are expressed as degrees Fahrenheit) - See PDF for table - See PDF for table

C =   Cold = waters with a fish and other aquatic life use designation of "cold water community"

W-L =   Warm -Large = waters with a fish and other aquatic life use designation of "warm water sport fish community" or "warm water forage fish community" and
  unidirectional 7Q10 flows ≥ 200 cfs (129 mgd)

W-S =   Warm - Small = waters with a fish and other aquatic life use designation of "warm water sport fish community" or "warm water forage fish community" and
  unidirectional 7Q10 flows 200 cfs (129 mgd)

LFF =   waters with a designation of "limited forage fish community"

NIL =   Northern Inland Lakes = applicable for those lakes north of State Highway 10

SIL =   Southern Inland Lakes = applicable for those lakes south of State Highway 10

MR =   Mississippi River = applies to any portion of Wisconsin's Mississippi River reach

RR =   Rock River = applies to waters downstream of Lake Koshkonong

UWR =   Upper Wisconsin River = applies to waters upstream of Petenwell Dam

LWR =   Lower Wisconsin River = applies to waters downstream of Petenwell Dam to the confluence with the Mississippi River

LFR =   Lower Fox River = applies to waters downstream of the Lake Winnebago outlet

SGB =   Green Bay waters south of the Brown County line to the Fox River mouth

NGB =   Green Bay waters north of the Brown County line to the northernmost point on Washington Island

SLM =   Lake Michigan waters south of the Milwaukee River mouth (downtown Milwaukee)

NLM =   Lake Michigan waters north of the Milwaukee River mouth (downtown Milwaukee)

LS =   Lake Superior = waters in Lake Superior except those in Chequamegon Bay

CB =   Chequamegon Bay = waters within the region enclosed by Chequamegon Point and a straight line west to the mainland

History: CR 07-111 : cr. Register September 2010 No. 657 , eff. 10-1-10; renumbering of (1) (b) 1. a. and b. made under s. 13.92 (4) (b) 1. , Stats., Register September 2010 No. 657 .