Ill. Admin. Code tit. 35 § 302.408

Current through Register Vol. 48, No. 49, December 6, 2024

Section 302.408 - Temperature

a) For the South Fork of the South Branch of the Chicago River (Bubbly Creek), the temperature must not exceed 34 °C (93 °F) more than 5% of the time, or 37.8°C (100 °F) at any time.

b) The temperature standards in subsections (c) through (i) will become applicable beginning July 1, 2018.

c) There must not be any abnormal temperature changes that may adversely affect aquatic life unless caused by natural conditions.

d) The normal daily and seasonal temperature fluctuations that existed before the addition of heat due to other than natural causes must be maintained.

e) The maximum temperature rise above natural temperatures must never exceed 2.8°C (5 °F).

f) Water temperature at representative locations in the main river must never exceed the maximum limits in the applicable table in subsections (g), (h) and (i), during more than one percent of the hours in the 12-month period ending with any month. The water temperature must not exceed the maximum limits in the applicable table that follows by more than 1.7°C (3.0°F).

g) Water temperature in the Chicago Area Waterway System Aquatic Life Use A waters listed in 35 Ill. Adm. Code 303.235 must not exceed the limits in the following table in compliance with subsection (f):

Months	Daily Maximum
	(° C)	(° F)
January	16	60
February	16	60
March	16	60
April	32	90
May	32	90
June	32	90
July	32	90
August	32	90
September	32	90
October	32	90
November	32	90
December	16	60

h) Water temperature in the Chicago Area Waterway System and Brandon Pool Aquatic Life Use B waters listed in 35 Ill. Adm. Code 303.240 must not exceed the limits in the following table in compliance with subsection (f):

Months	Daily Maximum
	(° C)	(° F)
January	16	60
February	16	60
March	16	60
April	32	90
May	32	90
June	32	90
July	32	90
August	32	90
September	32	90
October	32	90
November	32	90
December	16	60

i) Water temperature for the Upper Dresden Island Pool Aquatic Life Use waters, as defined in 35 Ill. Adm. Code 303.230, must not exceed the limits in the following table in compliance with subsection (f):

Months	Daily Maximum
	(° C)	(° F)
January	16	60
February	16	60
March	16	60
April	32	90
May	32	90
June	32	90
July	32	90
August	32	90
September	32	90
October	32	90
November	32	90
December	16	60

Ill. Admin. Code tit. 35, § 302.408

Amended at 39 Ill. Reg. 9388, effective 7/1/2015

Amended at 47 Ill. Reg. 4437, effective 3/23/2023