Lakes of Missouri Volunteer Program

1. University of Missouri-Columbia Lake Morphology and Hydrology Lakes of Missouri Volunteer Program The The Missouri Department of Natural Resources Region V11, US Environmental Protection Agency, through the Missouri Department of Natural Resources, has provided partial funding for this project under Section 319 of the Clean Water Act

2. Lake Morphology/Hydrology • Surface Area • Depth • Volume • Watershed Area • Flushing Rate

3. Surface Area • Depth • Volume • Watershed Area • Flushing Rate Surface Area Ranges from 6 to 53,814 acres in size, with a median of 103 acres.

4. Surface Area • Depth • Volume • Watershed Area • Flushing Rate Surface Area of Classified Lakes 30% of classified lakes are 20 acres or less in size. 10% are greater than 300 acres in size.

5. Depth(determined by dam height) • Surface Area • Depth • Volume • Watershed Area • Flushing Rate

6. Surface Area • Depth • Volume • Watershed Area • Flushing Rate Average Depth Ranges from 3.7 feet to 62 feet, with a median of 11.6 feet.

7. Why is depth important? • Shallow lakes may mix sporadically throughout the summer, leading to more internal loading of nutrients. • A deeper lake has a larger volume of water, which influences hydrology.

8. Lake Volume(determined by area and depth) • Surface Area • Depth • Volume • Watershed Area • Flushing Rate

9. Lake Volume Ranges from 48 to 2,700,000 acre-feet, with a median of 1,675 acre-feet. 1 acre 1 foot 1 acre-foot = 325,851 gallons

10. Surface Area • Depth • Volume • Watershed Area • Flushing Rate Same inflow volume, different Lake Volume Dam height and topography determine the lake volume

11. Watershed Area(catchment size) • Surface Area • Depth • Volume • Watershed Area • Flushing Rate

12. Watershed Area Ranges from 83 to > 4,000,000 acres, with a median of 2,516 acres.

13. Surface Area • Depth • Volume • Watershed Area • Flushing Rate Same size lake, but with different inflow volumes Inflow is determined by the watershed area and rainfall

14. Flushing Rate • Surface Area • Depth • Volume • Watershed Area • Flushing Rate - the proportion of the total lake volume that is replaced (per year) by inflowing water. Flushing Rate = Regional Runoff Coefficient * Watershed Area / Lake Volume

15. Flushing Rate • Surface Area • Depth • Volume • Watershed Area • Flushing Rate Ranges from 140 to 0.1, with a median of 1.1

16. outflow 50 inflow 50 Volume 100 inflow 100 outflow 100 Flushing Rate = 1 Volume 100 inflow 200 outflow 200 Volume 100 Annual Inflow / Volume = Flushing Rate Flushing Rate = 0.5 Flushing Rate = 2

17. Why is Flushing Rate important? Flushing Rate is used to gauge inputs relative to lake volume. A 100 acre lake with a low flushing rate has fewer inputs than a 100 acre lake with a high flushing rate.

18. Surface Area • Depth • Volume • Watershed Area • Flushing Rate Same lake volume, different Inflow Volume High Flushing Rate Low Flushing Rate

19. Surface Area • Depth • Volume • Watershed Area • Flushing Rate Same inflow volume, different Lake Volume High Flushing Rate Low Flushing Rate

20. Quick Ecoregion Overview

21. Missouri’s Physiographic Regions Glacial and Osage Plains Ozark Border Ozark Highlands

22. Average Phosphorus Values (for physiographic regions) Region Phosphorus (ug/L) Glacial Plains 44 Osage Plains 73 Ozark Border 40 Ozark Highlands 17