Missouri Thermal Discharges regulations & environmental compliance analysis

Missouri Thermal Discharges: What you need to know

Governing Law and Regulations

Thermal discharges: 10 Missouri Code of State Regulations (CSR) 20-7.031

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Habitats: 10 CSR 20-7.031(5)(D)(1) to 20-7.031(5)(D)(3)

Lakes: 10 CSR 20-7.031(5)(D)(4)

Mississippi River: 10 CSR 20-7.031(5)(D)(5)

Mixing zones: 10 CSR 20-7.031(5)(D)(6)

Regulatory Agency

Missouri Department of Natural Resources (DNR) Division of Environmental Quality Water Protection Program

See ADDRESSES & CONTACTS for addresses and telephone numbers.

See national section for basic information and federal regulations.

Comparison: State vs. Federal

Rules. Missouri has developed monthly and geographically specific temperature standards for effluent discharges in accordance with the federal Clean Water Act. The thermal discharge regulations are divided between cold and warm water habitats, lakes, and the three zones of the Mississippi River.

Administration and enforcement. DNR's Water Protection Program is responsible for the administration and enforcement of the state's thermal discharge regulations.

State Requirements



10 CSR 20-7.031(5)(D)(1) to 20-7.031(5)(D)(3)

Table 1 sets out the thermal discharge limitations (outside the mixing zone) for fisheries.

Table 1
  Discharge cannot raise or lower the temperature by more than Discharge cannot raise water temperature above
Warm water Habitats 5°F 90°F
Cool water Habitats 5°F 84°F
Cold water Habitats 2°F 68°F

Note: Site-specific alternate temperature requirements may be considered by the DNR in cases where sensitive aquatic species are resident.


10 CSR 20-7.031(5)(D)(4)

Water contamination may not cause any measurable rise in the temperature of lakes. Temperature increases are allowed for Lake Springfield, Thomas Hill Reservoir, and Montrose Lake. ...

Read more about Thermal Discharges