1. Water Treatment Plant General Discharge Permit
Kelli D. Buscher, P.E.
SD DENR

2. Clean Water Act Background
Clean Water Act established the National Pollutant Discharge Elimination System (NPDES) Program

3. Clean Water Act Background
All “Point Sources”
“discharging pollutants”
into “waters of the US”
must obtain a discharge permit

4. Clean Water Act Background
A discharge permit is required to use public resources for waste disposal and limits the amount of pollutants that may be discharged
The discharge of pollutants to waters is a privilege, not a right

5. Clean Water Act Background
All “waters of the state” have water quality standards
A water quality standard defines the water quality goal of a water body by designating the beneficial use or uses of the water body and by setting criteria necessary to protect those uses

6. Beneficial Uses (1) Domestic Water Supply Waters;
(2) Coldwater Permanent Fish Life Propagation;
(3) Coldwater Marginal Fish Life Propagation;
(4) Warmwater Permanent Fish Life Propagation;
(5) Warmwater Semipermanent Fish Life Propagation;
(6) Warmwater Marginal Fish Life Propagation;

7. Beneficial Uses (7) Immersion Recreation Waters;
(8) Limited Contact Recreation Waters;
(9) Fish and Wildlife Propagation, Recreation, and Stock Watering Waters;
(10) Irrigation waters; and
(11) Commerce and Industry Waters.

8. What Needs to be Covered?
Treatment system overflows
Filter Backwash and Settling Basins
Disinfection and Flushing of Water Lines
Storage system disinfection and overflows
Water line breaks
Other WTP Discharges that fit the limits and management practices

9. Why a General Permit?
Ensure all discharges from water treatment systems are covered
Establish uniform criteria for discharges from these activities
Reduce the administrative time for permit authorization
Facilitate the scheduling of activities by reducing the administrative time for permit authorization;
Establish uniform criteria for management practices and effluent limits for discharges from these activities; and
More consistent permitting and enforcement with respect to these discharges.

10. What is NOT Covered? If the discharge contains radioactive components
If the discharge is to a lake or POTW
If the discharge is a significant contributor of pollution
If the discharge presents a health hazard
If the discharge is not in compliance

11. What is NOT Covered?
If EPA develops federal limits for water treatment plant discharges
If a water quality management plan containing requirements applicable to the discharges is approved
If conditions or standards have changed so that the discharge no longer qualifies for the general permit.

12. Prohibitions No discharge of sanitary wastewater
No direct discharge of solids and/or sludges
No discharge of floating solids or visible foam
No discharge of toxic pollutants in toxic amounts
SDDENR must be notified in advance of all chemicals used
Prevent or minimize stream scouring or bank erosion caused by the discharge

13. Limits pH 6.5-9.0 for most discharges
for coldwater marginal fisheries
for coldwater permanent fisheries

14. Limits Total Suspended Solids Total Dissolved Solids 90 mg/L for most
30 mg/L for coldwater permanent fisheries
Total Dissolved Solids
2,500 mg/L for most
1,000 mg/L for domestic water supplies

15. Limits Conductivity Chlorinated water Chloraminated water
2,500 μmhos/cm
Chlorinated water
0.05 mg/L Total Residual Chlorine
Chloraminated water
1.0 mg/L Ammonia

16. Outfalls DW1 Raw or partially treated water from the treatment system
Lime softening ponds
Filter backwash
Overflows from treatment units
Raw water

17. Outfalls
DW2
Completely treated water from treatment, storage, or distribution
Storage system overflows
Water line breaks
Hydrant flushing
Hydrostatic testing
Disinfection of new lines

18. Monitoring Requirements
Outfall DW1
Flow
Duration of Discharge pH
Temperature
Total Fluoride
Sulfates
TSS
TDS
TRC (if chlorinating)
Ammonia (if chloraminating)
Conductivity
Alkalinity

19. Monitoring Requirements
Outfall DW2
Total Flow
Duration of Discharge pH
TSS
TRC (if chlorinating)
Ammonia (if chloraminating)

20. Best Management Practices
Permit requires the development of a BMP plan
Describe what will be done to reduce pollution from temporary discharges such as overflows and line flushing

21. Representative Outfalls
Representative outfalls cover activities at similar sites
Sampling would only have to be performed at selected outfalls
Provide documentation showing that the discharges from these activities will be similar in quality and nature

22. Frequently Asked Questions
Are all water systems required to get coverage under the discharge permit?
Do all water systems need coverage under both outfalls?
How is the state going to handle chlorine for discharges into road ditches?
What if we can not get a sample during a discharge?

23. Frequently Asked Questions
The permit requires that no chemicals be added without DENR notification. How will that work?
Can we use chemicals for dechlorination?
Why would I want coverage under this permit instead of the temporary one?
What are the next steps?

24. For more information Kelli Buscher Anthony Mueske
Anthony Mueske