Numeric Criteria Development

The information presented below gives a summary of state progress towards the development of numeric criteria. The information comes from EPA’s “State Adoption of Numeric Nutrient Standards (1998-2008)” report, current water quality standards, program activity measures, and nutrient criteria development plans. Links to the Illinois’s Nutrient Criteria Plan and state water quality standards are also provided.

• Existing Numeric Criteria
• Links to the Plan and Criteria
• Milestone Information

Existing Numeric Criteria

S = Statewide    W = For selected waterbody    N ⁄ A=Not Applicable

Note: See Statewide Criteria and Site-specific Criteria tabs for more information.

Top of Page

Links to Numeric Nutrient Criteria Plan and Existing Nutrient Criteria

Plans:

• Nutrient Criteria Development Plan for the State of Illinois 2006

• ORSANCO Nutrient Criteria Plan September 2011
• ORSANCO Nutrient Criteria Plan March 2011

WQS: Illinois Water Quality Standards
Environmental Regulations for the State of Illinois: Title 35 of the Illinois Administrative Code Exit

Top of Page

Milestone Information

Milestone information updated July 2012.

TN: Total Nitrogen; TP: Total Phosphorus

Note: Illinois has identified phosphorus as the typical limiting nutrient and will not pursue nitrogen criteria until after phosphorus criteria are adopted.

Top of Page

Statewide Criteria

The information on this tab shows EPA-approved nutrient criteria for Illinois’s waterbodies. The language presented below comes directly from state water quality standards and applies to all waterbodies within the state (unless a waterbody type or designated use is noted). Criteria applicable to specific waterbodies within the state can be found on the “Site-specific Criteria” tab. For more information, refer to the Illinois water quality standards.

The following information reflects Illinois’ water quality standards posted to the Water Quality Standards Repository as of November 2010 (EPA-approved March 2009).

Subpart B: General Use Water Quality Standards

Section 302.203 Offensive Conditions
Waters of the State shall be free from sludge or bottom deposits, floating debris, visible oil, odor, plant or algal growth, color or turbidity of other than natural origin. The allowed mixing provisions of Section 302.102 shall not be used to comply with the provisions of this Section.

Subpart C: Public and Food Processing Water Supply Standards

Section 302.304 Chemical Constituents

The following levels of chemical constituents shall not be exceeded:

Subpart D: Secondary Contact and Indigenous Aquatic Life Standards

Section 302.403 Unnatural Sludge
Waters subject to this subpart shall be free from unnatural sludge or bottom deposits, floating debris, visible oil, odor, unnatural plant or algal growth, or unnatural color or turbidity.

Subpart E: Lake Michigan Basin Water Quality Standards

Section 302.515 Offensive Conditions
Waters of the Lake Michigan Basin must be free from sludge or bottom deposits, floating debris, visible oil, odor, plant or algal growth, color or turbidity of other than natural origin. The allowed mixing provisions of Section 302.102 shall not be used to comply with the provisions of this Section.

Site-specific Criteria

The information on this tab shows EPA-approved site-specific nutrient criteria for Illinois’s waterbodies. Criteria on this page apply only to the waterbodies listed below. Criteria applicable to all waterbodies within the state are found on the “Statewide Criteria” tab. For more information, refer to the Illinois water quality standards.

The following information reflects Illinois’ water quality standards posted to the Water Quality Standards Repository as of November 2010 (EPA-approved March 2009).

Subpart B:General Use Water Quality Standards

Section 302.205 Phosphorus
Phosphorus (STORET number 00665): After December 31, 1983, Phosphorus as P shall not exceed 0.05 mg/L in any reservoir or lake with a surface area of 8.1 hectares (20 acres) or more, or in any stream at the point where it enters any such reservoir or lake. For the purposes of this Section, the term "reservoir or lake" shall not include low level pools constructed in free flowing streams or any body of water which is an integral part of an operation which includes the application of sludge on land. Point source discharges which comply with Section 304.123 shall be in compliance with this Section for purposes of application of Section 304.105.

Subpart E: Lake Michigan Basin Water Quality Standards

(Source: Amended at 23 Ill. Reg. 11249, effective August 26, 1999)

Section 302.504 Chemical Constituents
The following concentrations of chemical constituents must not be exceeded, except as provided in Sections 302.102 and 302.530:

c) In addition to the standards specified in subsections (a) and (b) of this Section, the following standards must not be exceeded at any time in the Open Waters of Lake Michigan as defined in Section 302.501.

Section 302.515 Offensive Conditions
Waters of the Lake Michigan Basin must be free from sludge or bottom deposits, floating debris, visible oil, odor, plant or algal growth, color or turbidity of other than natural origin. The allowed mixing provisions of Section 302.102 shall not be used to comply with the provisions of this Section.

(Source: Added at 21 Ill. Reg. 1356, effective December 24, 1997.)