1. Predicting HAB Strength (Western Basin) Pete Richards NCWQR-HU

2. Western Basin Algae Problems Tom Bridgeman, U. Toledo Cladophora and noxious “ blue- green algae ” are back with a vengeance! City of Toledo - $3000/day to treat drinking water for microcystin. Microcystin 1000 ppb in Western Basin, 2000 ppb in Grand Lake St. Marys. WHO recommendations 1 ppb for drinking water (20 ppb for swimming)

3. Microcystis in Lake Erie The Microcystis-Anabaena bloom of 2009 was the largest in recent years in our sampling region 2011 …until 2011

5. Predicting: Concept P loading drives algal growth HABs occur in late summer Perhaps P loads in some seasons are more important than loads in others.

6. Relate “cyanobacteria index” (CI) to discharge and P loading CI best predicted by March-June discharge March-June TP and DRP also predictive Initial work done late in 2011 – can we predict 2012? NOAA work

7. 2011 and 2012 are the extremes - 2012 is 20% of 2011! Spring Discharge (March-June) NOAA Ecofore/Maumee Loads.xls

8. 2011 and 2012 are extreme - 2012 is 17% of 2011! Spring TP Load NOAA Ecofore/Maumee Loads.xls

9. 2011 and 2012 are extreme - 2012 is 15% of 2011! Spring DRP Load NOAA Ecofore/Maumee Loads.xls

10. 2012 Forecast (mild bloom) and Observed Bloom 2012 Forecast Measured

11. 08/30/2012 (DOY=243) 09/03/2011 (DOY=246)

12. Learnings 2012 does not mean we’ve solved the problem! It does show that the lake is responsive to P loadings in a short timeframe. It shows that internal resuspension is not a major factor It shows that the Detroit River inputs are not a major factor.

13. What about 2013? Spring totals just completed at end of June Predictions given July 2 at a webinar at OSU’s Stone Lab

14. March-June Maumee Discharge 2.77

15. March-June Maumee Total P 1,099

16. March-June Maumee DRP 238

17. 2013 Forecast: Significant bloom, similar to 2003, much milder than 2011 2013

18. 2013 prediction for western Lake Erie similar in intensity to 2003, <1/5 of 2011 lowmedium high concentration 2013 may resemble 2003 2011 for comparison

19. NOAA Lake Erie Harmful Algal Bloom Bulletin, 2013, 5 th year Sign up to receive the weekly bulletin Search for NOAA Lake Erie Bloom Bulletin

20. October 7, 2011