Special Honeoye Lake Algae Presentation 9/14/2010
Thank you to the more than 160 residents and guests who turned out for the Town Board Meeting featuring special guests Dr. Bruce Gilman, Dr. Steve Souza, and Jack Starke. From the extremely informative presentations, many of our residents' questions were answered. We appreciate the input and thoughtful questions brought forward by the community as we continue to explore the collaboration of State, County, Town, and citizens to benefit Honeoye Lake. Thank you to Dr. Gilman, Dr. Souza, and Mr. Starke for their research and time.
NYS Department of Health Algae Information
Facts about Harmful Algal Blooms
DEC Open Burning Regulations
Aquatic Weed Survey
Below please find an explanation from Bruce Gilman regarding the lake conditions. Bruce is an FLCC Environmental Conservation Department professor and the Director of the Muller Conservation Field Station.
To manage the nutrient budget of Honeoye Lake, we have to consider all the ways that phosphorus and nitrogen enter the lake, and try to control those ways, as well as consider activities that we can pursue to remove or inactivate phosphorus that is already in the lake basin. The lake has a nutrient cycle similar to your home vegetable garden. There is a large supply of nutrient already present in the soil, or in the lake's case, in the bottom substrate. I completed a bottom coring research study a few years ago that scientifically documented the total phoshorus, and the portion of it that is readily available, in 33 different locations within the lake. We collectively call this phosphorus the "legacy phosphorus". Our cores were deep enough to reach back in time about 300 years. There is a large amount of nutrient stored in the deep lake sediment that will return to the water when the dissolved oxygen levels near the bottom are low. We call this part of the nutrient cycle the internal loading because it originates within the lake. The alum application was designed to reduce the amount of internal loading. Returning to the vegetable garden analogy, if we find poor plant growth in our garden, we may choose to enhance our crop growth by adding fertilizer to the soil. Similarly, we know that certain watershed activities will enhance the delivery of nutrients to Honeoye Lake, whether it be flowing through a tributary stream or directly across the landscape. We call this portion of the nutrient cycle the external loading. The intensity of storm events, combined with the total rainfall in the event, influences greatly how much erosion takes place and the quantities of soil and nutrients moving to the lake. The impact of our human activities in the watershed are also important. We have completely mapped all of the human land use patterns and natural land cover features in the watershed, and these have been used to predict the potential for nutrient pollution to the lake. What is difficult to predict is the frequency of severe storms, like the one occuring on July 13, 2010, that delivered slightly over 4 inches of rainfall in 30 minutes across the southwestern edge of the lake! You may recall that County Road 36 was closed the following day and that the cleanup is still ongoing six weeks after the storm. We have also sampled tributary streams during periods of storm runoff and our now working on a State sponsored inventory of the streams to identify locations where stream banks need to be stabilized.
Managing the nutrient budget of any lake is complex; everyone needs to be involved and supportive of the multiple measures that are required. Gut reactions, exaggeration of situations and untruths about management activities will distract us from our common goal of restoring lake health. As a scientist, I realize that there are still many things that we need to learn about the functioning of Honeoye Lake. There will be no "silver bullet", no simple cure for the lake conditions we often see in the late summer. But through multiple techniques, like removing nutrients from the lake in the form of mechanically harvested weeds, chemically binding nutrients in the deep sediment, improving stormwater management, and encouraging people to use only phosphorus free fertilizers on their lawns, we may effectively begin to manage the nutrient budget.