Clinton Lake Sedimentation

1. Clinton Lake Sedimentation Earl Lewis Kansas Water Office

2. History of Clinton Lake • Multipurpose operation - November 30, 1977 • Authorized by Flood Control Act of 1962 • Water supply storage included at request of State of Kansas under 1958 Water Supply Act - 89,200 AF • U.S. Fish & Wildlife requested storage for low flow augmentation - 21,200 AF

3. Sediment Allocation • Original 100 year sediment allocation 28,500 AF, or 285 AF/year • Sediment allocation • 19,000 AF - conservation pool • 9,500 - flood control pool • 1991 Corps survey showed 296 Af/yr loss in conservation pool • Virtually no loss in flood pool

4. Yield Analysis • Water Marketing Act requires that Kansas Water Office be able to deliver water through a drought having a 2% chance of recurrence in any one year • By regulation, defined as a repeat of the 1952-1957 drought period

5. Yield Analysis • Major factors in yield analysis • Inflow • Evaporation • Sedimentation (storage available) • Downstream senior water right holders • Low flow releases

6. 2004 Yield Analysis

7. Water Quality • Kansas Biological Survey report that indicates flats developed by siltation causing additional algae blooms and water quality concerns. • During low flow periods decomposition of the algae blooms cause taste and odor problems.

9. Potential Ways to Deal with Sediment • Reduce sediment load coming into lake • Raise conservation pool level to offset uneven sediment distribution • Dredge sediment in lake

10. Clinton Lake Watershed

11. Watershed Restoration and Protection Strategy • Developed by a committee of local stakeholders, sponsored by the Kaw Valley Heritage Alliance • City of Lawrence, county conservation districts, the Natural Resources and Conservation Service, K-State Extension, Health and Environment, and the Biological Survey • Recommendations to reduce sediment and associated pollution from both agricultural and urban sources

12. Watershed Restoration and Protection Strategy • Current activity is development of a plan to identify and restore eroding stream banks in the Deer Creek watershed • Stream bank restoration will reduce sedimentation into the lake

13. Streambank Stabalization

14. Storage Reallocation • State contract with Corps requires storage reallocation if sediment distribution incorrect • Move flood to conservation storage • Reallocation costs approx. $1,000,000 • Plus mitigation costs • Currently underway at John Redmond

15. Kansas Water Authority Lake Restoration Policy • Approved November 2004 • Conduct small lake dredging project • Review El Dorado and Oologah studies • Develop predictive model for determining the occurrence and duration of algal blooms • Clean Drinking Water Fee should be used as one funding source for restoration projects

16. Dredging • South Dakota small lakes program - $5,600/AF • At 296 AF/year loss - $1.66 million/year to keep up

17. Summary • Clinton Lake conservation pool is silting in 36% faster than anticipated. • Clinton Lake as a whole is silting in only 11 AF/year faster than projected. • Reallocation under the federal contracts will keep design water supply capacity whole through the year 2073.

18. Summary • First action - reduce sediment load into lake • City of Lawrence should continue and increase WRAPs efforts • Dredging potentially solves both quality and quantity issues • Dredging is more expensive than other alternatives