Water Quality Data
Collecting water quality data on a lake over many years is important to understand how our lake is doing. Many years of data collection is needed to establish a trend line based on all the variables that impact water quality. No single year worth of data is enough to establish a trend line. Therefore, decisions on how to manage a lake should be based on long term data. There has been some long term water quality data collected in the lake, although it hasn’t been consistently collected year to year. In addition, very little data has been collected on the tributaries that flow into Hess Lake. According to a 1982 Study done by Edmands Engineering, 57% of the water and 54% of the phosphorus comes into Hess Lake from Wheeler Drain (see this study under the Engineering tab). Additional engineering studies done in the 1990’s agree with this assessment. I know reviewing water quality data can be very boring. However, data is used to make decisions on how to improve the water quality of a lake.
The Environmental Protection Agency, (EPA) a federal agency, has listed Hess Lake as an Impaired Lake for nutrient pollution.
Experts refer to nutrient loading of a lake as external nutrient loading and internal nutrient loading. Examples of external nutrient loading to the lake would be, nutrients from Wheeler & Alger Drains, runoff from lawns, septic systems, and from the atmosphere. Internal nutrient loading are nutrients stored in the sediment of the lake.
A few words about Water Quality Data
I will try to keep this discussion about water quality data non-technical as possible.
In reference to collecting water quality data, the following was stated, on page 9 of the 2020 Progressive AE Hess Lake Management Plan, “There are many ways to measure lake water quality, but there are a few important physical, chemical and biological parameters that indicate the overall condition of a lake. These measurements include temperature, dissolved oxygen, total phosphorus, chlorophyll-a and secchi transparency.”
In addition, Water Quality Data collected on Wheeler & Alger Drains should include Total Phosphorus, Nitrates, water flow rate and additional parameters when required to identify an issue. Note: Nitrates isn’t currently being collected.
If you would like to understand Water Quality Data, please see attached PDF listed below on Water Quality Definitions.
Since Phosphorus is generally what fuels Harmful Algal Blooms, this data is important, although Nitrates could contribute. Generally, Total Phosphorus Numbers that exceed 20 ug/L are an issue. Keep this number in mind when reviewing Total Phosphorus Data.
Dissolved Oxygen is another important indicator. Lakes need a minimum of 5 mg/L to support warm-water fish. In addition, oxygen is needed to keep phosphorus from releasing into the water column from the sediment in the bottom of the lake. Looking at the data, you will see that, excluding the three deep basins in the lake, that Hess Lake Waters are well oxygenated. However, in late summer you will see that near the bottom of the lake in the three deep basins, that oxygen levels are depleted, which could release phosphorus into the water column and fuel Harmful Algal Blooms. This is called internal nutrient loading.
For a more technical explanation of water quality data, please see pages 10 to 17 in the 2020 Progressive AE Hess Lake Management Plan. This complete study is located under the Engineering Tab of this website.
So, what does all this data mean? Essentially Hess Lake has too much phosphorus coming into our lake and fueling Harmful Algal Blooms, or in the past, supporting an abundance of aquatic plants. In order to improve our lake, we must all work together to reduce the amount of nutrients from going into our lake. This would include, eliminating all lawn fertilizers, adding a buffer strip or green zone between the waters edge and your lawn to filter out nutrients from going into the lake, and maintaining your septic system. In addition, Progressive AE our management company, and our lake board, must find a solution to significantly reduce the amount of nutrients from coming into the lake from Wheeler and Alger Drains. Past studies have indicated that these two drains are the two top contributors of nutrients to the lake.
There are approximately 384 lakeside parcels. About 88% of these parcels have some form of seawall, which according to the experts, impacts the ecology of our lake. Consider removing or modifying your seawall. Any work done on your shoreline/seawall requires a permit from EGLE. Please see Shoreline Guidelines Tab on this website for ideas on what to do with your shoreline.