Causes and Possible Corrections for Nuisance Algae Conditions in Huron River Lakes: Summary Findings from 23, 24, and 25 Prof John T. Lehman Middle Huron Partners 8 November 25 Welcome Summary of public opinion survey results Scientific findings from river sampling: source and sink regions Scientific findings from lake sampling Seasonal patterns Bloom dynamics and triggering mechanisms Algal toxins in Ford Lake and Barton Pond Possible remediation experiments Questions from Middle Huron Partners Possible next steps- general discussion Adjournment
Summary of Public Opinion Survey Returns to Date Questionnaires distributed to 25 households near Ford and Belleville Lakes 673 responses to date 4 Demographic Information What is your age? (656 responding) Percent 35 3 25 2 15 1 5 18-29 3-45 46-61 62+
What is your highest level of education? (649 responding) 25 2 Percent 15 1 5 High School Trade School Some College 2-Year 4-Year Grad School Postgrad What is your ethnicity? (621 responding) 1 8 Percent 6 4 2 African American Asian Biracial Caucasian Latino Native American
5 What is your annual income? (528 responding) 4 3 Percent 2 1 <$15, $15,- $35, $35,- $5, $5,- $75, >$75, Have you noticed excessive algae growth in the Huron River, Ford Lake, or Belleville Lake? (642 responding) Yes = 73.8% If so, when did you notice it? Yes, 24 68.% Yes, 23 64.2% Yes, 22 52.1% Yes, 21 44.6%
Has the environmental water quality of the Huron River and lakes stopped you from swimming or affected other forms of contact recreation? (652 responding) Yes 55.3% 3 On a scale of 1-5 (with 5 being a major problem) how would you rank the algae nuisance problem in your area? (534 responding) 2 Percent 1 1 2 3 4 5
Do you think that the current efforts to improve the water quality of the Huron River, Ford Lake and Belleville are too little, too much, or about right? (566 responding) 6 4 Percent 2 Too Little Too Much About Right Don't Know Would you favor increasing efforts to improve water quality in Huron River, Ford or Belleville Lake, even if it resulted in an increase of municipal taxes? (553 responding) 79.2% said Yes By how much? Percent 35 3 25 2 15 1 5 28.3 28.3 23.6 13.4 8.4 $2 $5 $75 $1 $1+
On a scale of 1-5 (with 1 being of highest priority), where should money be allocated to repair damage? 4 3 Restoration of Wildlife Areas (49 responding) 4 3 Replenish Fish Populations (499 responding) Percent 2 Percent 2 1 1 1 2 3 4 5 1 2 3 4 5 Percent 8 6 4 Reduce Water Pollution (539 responding) Percent 4 3 2 Remove Nuisance Aquatic Vegetation (511 responding) 2 1 1 2 3 4 5 1 2 3 4 5 River Sampling: Source and Sink Regions Upstream Boundary: Zeeb Rd Time Frame: June 23 to Sept 25
How much fertilizing nutrient entered the study region? (kilograms) Total P Dissolved P Total N Nitrate Jun 3 to Sep 5 219 14 114 64 Jun-Sep only 66 35 217 86 What is the ratio of fertilizing nutrient entering Ford Lake compared with the amount that entered the study region? Total P Dissolved P Total N Nitrate Jun 3 to Sep 5 2.2 2.5 1.8 2.2 Jun-Sep only 2.5 2.8 2.2 3.8
How did nutrients in the river change from point to point down the river? KG TP Change from Zeeb 3 25 2 15 1 5 June 23 to Sept 25: Entire Study TP HR2 HR3 HR4 HR5 HR6 HR7 HR8 HR9 HR1 HR12
How did nutrients in the river change from point to point down the river? 12 1 June to Sept only KG TP Change from Zeeb 8 6 4 2 TP -2 HR2 HR3 HR4 HR5 HR6 HR7 HR8 HR9 HR1 HR12 How does catchment area increase from point to point down the river? 1 9 Increase in catchment area (km 2 ) 8 7 6 5 4 3 2 1 HR2 HR3 HR4 HR5 HR6 HR7 HR8 HR9 HR1 HR12
How did DP in the river change from point to point down the river? 18 16 June 23 to Sept 25: Entire Study KG DP Change from Zeeb 14 12 1 8 6 4 DP 2 HR2 HR3 HR4 HR5 HR6 HR7 HR8 HR9 HR1 HR12 How did DP in the river change from point to point down the river? 7 6 June to Sept only KG DP Change from Zeeb 5 4 3 2 1 DP -1 HR2 HR3 HR4 HR5 HR6 HR7 HR8 HR9 HR1 HR12
What fraction of AAWWTP discharge is still present at HR7 (Superior Rd), assuming that all added DP is from the AAWWTP? Jun 3 to Sep 5: 71.3% Jun-Sep 3, 4, 5: 61.8% Of the net quantity of phosphorus added to the Huron River between Zeeb Road and Ford Lake, how much can be ascribed, at maximum, to the AAWWTP? Jun 3 to Sep 5: 52% Jun-Sep 3, 4, 5: 59%
Results from Lake Sampling Is external P loading the cause of the cyanobacteria blooms that plague Ford Lake during late summer? Exploit unplanned experiments, e.g. the blackout of 23. 6 25 mol/d TP discharge 5 4 3 2 1 TP discharge phycocyanin 2 15 1 5 µg L -1 Phycocyanin 8/1/3 9/1/3 1/1/3
mol/d TP discharge 6 5 4 3 2 1 TP discharge phycocyanin 25 2 15 1 5 µg L -1 Phycocyanin µm TP 8/1/3 9/1/3 1/1/3 7 m 1 m 6 5 4 3 2 1 8/1/3 9/1/3 1/1/3 Factors that favor cyanobacteria High temperatures and low wind Large supply of phosphate Low ratio of nitrogen to phosphorus Ammonium as a nitrogen source
Usual assumption-- algae nuisance in Ford Lake is caused by phosphate in the Huron River, particularly by phosphate discharged from wastewater treatment facilities. Thinking thus, State regulators have imposed ever stricter discharge limits on WWTPs. There is evidence that this management approach, though socially conscious, has had no beneficial effect on Ford Lake despite years of effort and millions of dollars. Nuisance problems in Ford Lake are caused by floating surface blooms of bluegreens.
2 15 TN:TP phycocyanin F1 8 6 1 4 5 2 2 F2 15 TN:TP (mol:mol) 15 1 5 1 2 1 µg L -1 PC 2 15 F3 5 4 1 3 2 5 1 Jun Jul Aug Sep Oct
TN:TP (mol:mol) 12 1 8 6 4 2 Barton Pond TN:TP phycocyanin Jun Jul Aug Sep Oct 2 15 1 2 1 µg L -1 PC FL1 FL2 FL3
Seasonal Changes in Water Transparency Clear Water Phase Bluegreens
Possible Remediation Experiments Selective Depth Withdrawal Destratification Biomanipulation
28 C lots of oxygen 26 C no oxygen Ford Lake Dam $ Hydro power Potential dead fish <5 m >5 m
Simple Model Steep sided linear basin West end- 1 compartments, 5 m deep at maximum East end- 1 compartments 5 m deep, 1 compartments deeper than 5 m Simulate actual oxygen Use actual discharge data from dam, courtesy of Ypsilanti Charter Township
18 16 14 12 mg/l DO 1 8 predicted 7 m observed 6 4 9 m 2 1-Jan 1-Feb 4-Mar 4-Apr 5-May 5-Jun 6-Jul 6-Aug 6-Sep 7-Oct Simulate alternative scenario Same water discharge total For 1 weeks starting June 1: Send enough through turbines to generate minimum power output each day (135 CFS required) Discharge the rest through the bottom gates.
18 16 14 1 Weeks Minimum Power Generation Starting Jun 1 mg/l DO 12 1 8 6 Predicted 4 2 1-Jan 1-Feb 4-Mar 4-Apr 5-May 5-Jun 6-Jul 6-Aug 6-Sep 7-Oct Considerations: expense, navigation hazards, fouling Destratification- Biomanipulation- Considerations: expense, feasibility, unexpected outcomes
Belleville Lake Current on-going research: Find the optimal solution to generate maximum revenue from hydroelectricity while maintaining sufficient oxygen to prevent algal blooms. The optimal solution will be a function of weather, and therefore the solution must be adaptive.
Questions from Middle Huron Partners What is the best way to monitor the Huron River in the future? Should lakes and impoundments over a certain depth limit be assigned individual TMDLs? What is the proper balance between mitigation of P inputs upstream versus in the lakes themselves? (all of these questions lie outside of strict science because they include implicit human value judgment; perfect topics for discussion and citizen engagement) Possible Next Steps: Would MDEQ issue a variance on the current dissolved oxygen limit of 5 mg/l in the tailrace of the Ford Lake dam so that selective withdrawal could be experimented with during summer 26?
Additional Information: www.umich.edu/~hrstudy