Current and Upcoming Issues Confronting Inland Lakes Alan Steinman, Ph.D.

1. Current and Upcoming Issues Confronting Inland Lakes Alan Steinman, Ph.D. Annis Water Resources Institute, GVSU

2. Major Issues • Nonpoint source pollution / Stormwater runoff • Invasive species • Landscaping: good, bad, and downright pitiful

3. Nonpoint Source Pollution Nonpoint source (NPS) pollution comes from diffuse sources, such as septage, or rainfall and snowmelt moving over and through the ground.

4. Nonpoint Sources of Pollution • Excess fertilizers, herbicides, and insecticides • from agricultural lands and residential areas • Sediment from improperly managed • construction sites, crop and forest lands, and • eroding streambanks • Livestock, pet wastes, faulty septic systems, • atmosphere • Oil, grease, and toxic chemicals from stormwater • runoff

6. Harmful Algal Blooms (HABs) • Microcystin is the most common cyanotoxin produced by HABs → hepatoxin and tumor promotor. • The U.S. currently has no national standards for exposure to microcystin or other algal toxins. • WHO standards: • - drinking water: 1 µg/L • - recreational: 20 µg/L Data: Rick Rediske, AWRI

7. Stormwater Facts • Most of the NPS pollution comes during storm events • Stormwater discharges are generated by runoff from land and impervious areas during rainfall and snow events • Paved streets • Parking lots • Building rooftops

8. Why Should We Care about Stormwater? • Reduced recharge to aquifers • Increased erosion & sedimentation • Potentially toxic to stream biota • Cost of infrastructure

9. Stormwater Examples

11. Land Use Change Analysis -8.71% +121.36% -42.32% +79.40%

14. Solutions • Low Impact Development (LID) practices • Design natural infiltration to occur as close as possible to the original area of rainfall • Engineer terrain, vegetation, and soil features to optimize natural infiltration, allowing the landscape to retain more of its natural hydrological function • Best management practices, including riparian buffers, swales, rain gardens…

15. Invasive Species • 1 new species arrives ~ 8 months1 • change in fish prey/food webs • economic costs 1Ricciardi, A. 2001. CJFAS 58: 2513-2525.

16. Data: Tom Nalepa, GLERL

17. Diporeia Data: Tom Nalepa, GLERL

18. Food Web Changes: Lake Michigan Data: USGS, Great Lakes Science Center

19. Asian Carp Bighead Carp: • feeds mostly on plankton, including both zooplankton and large, colonial phytoplankton (e.g. cyanobacteria) • ecological concern over food web changes

20. Silver Carp • feeds mostly on phytoplankton • ecological concern over food web changes

21. Actual asian carp found From: Asian Carp Control Strategy Framework (Feb. 2010)

22. River length requirement • all locations currently with confirmed, self-sustaining populations of bighead, silver, grass, or black carp have access to a large river, with at least 80 km that are free-flowing

23. Vulnerable river systems? • Kolar et al. (2007) identified 22 GL rivers “that may be suitable for spawning” based on lack of dams and minimum length of 100 km • 7 of the 22 are in Lake Michigan: • 2 in the U.P. • 2 in WI • St. Joseph, Grand, and Pere Marquette

24. Drowned rivermouths that could serve as good adult feeding habitat

25. Nico et al. 2005

26. Upstream spawning behavior • don’t really know how far they move • usually associated with rapidly • increasing flows • big unknown and serious mgm’t need

27. Spawning location • thought to be in turbulent areas of • rivers • mouths of tributaries • probably not in small tributaries • may occasionally spawn in lakes, • but eggs not thought to survive

28. Nico et al. 2005

29. Are They a Threat to the Great Lakes? • Can tolerate colder water, but Great Lakes temperature regime may be a metabolic limitation • Need substantial amounts of plankton, so restricted to coastal, riverine areas • Can they move from one riverine area to another?

30. Submerged Aquatic Vegetation

32. Submerged Aquatic Vegetation

33. Hydrilla

34. Hydrilla • Grows up to 1 inch/day • Forms dense mats that block sunlight, • killing off native plants below • Dense mats inhibit boating, • swimming, & skiing • Slows movement of water, • allowing sediment to build • Poor fish habitat • Found close to MI

35. http://www.miseagrant.umich.edu/

36. Solutions • Need clear policy that prevents new invasive species from entering Great Lakes • Need early detection monitoring program in most vulnerable locations—quarantine and eradication likely to be successful

37. Landscaping Issues

38. Minimize lawn area • Establish “greenbelt” Courtesy: Progressive AE

39. Don’t add phosphorus fertilizer Don’t dump in storm drains Maintain greenbelt of trees Small lawn area Build a raingarden Don’t dump in storm drains Establish a greenbelt Courtesy: Progressive AE

40. Minimize hardened shorelines Seawalls deflect waves; scour lake bottom Seawalls prevent animal movement(frogs) Some exotic plants prefer disturbed habitat Seawalls provide poor habitat Courtesy: Progressive AE

41. 10 Ways to Protect Your Lake: 1) Use no-phosphorus fertilizer 2) Use minimum am’t of recommended fertilizer 3) Apply fertilizer to lawn, not sidewalk 4) Don’t feed waterfowl near lake

42. 10 Ways to Protect Your Lake: 5) Don’t burn leaves/clippings near lake 6) Plant buffer strip at lake’s edge 7) Promote runoff infiltration 8) Maintain wetlands

43. 10 Ways to Protect Your Lake: 9) Maintain your septic system 10) Don’t be complacent

44. Websites for more information: • www.michiganlakeinfo.org • www.shoreline.msu.edu • www.raingardens.org

45. www.gvsu.edu/wri