Collecting Water Samples in the Old Ausable Channel
What do we test for and Why?
The Ausable Bayfield Conservation Authority and Pinery Provincial Park collected water samples to test the water quality of the Old Ausable Channel monthly from March – November 2006. There is a need for water quality data from the Old Ausable Channel (OAC). Prior to 2006, very little was known about the water quality in this water body. It was assumed that the water quality was “good’. However, agencies had no data to indicate the current conditions.
The collection of water quality samples in 2006, showed that water conditions in the OAC were much better than in the surrounding landscape (Figures 1, 2 & 3). The ongoing collection of water quality data will help to guide management decisions and is also important to track changes over time. For example, the nutrients (nitrogen and phosphorus types) could be a very important determinant of plant growth in the OAC. There are species at risk fishes that live in the OAC that are dependent upon some of the vegetation types that grow in the channel. Also the Escherichia coli (E. coli) numbers and nutrient concentrations may help to explain land use decisions (i.e., possible septic system leachate or lawn fertilizer input from the residential areas along the OAC). Collecting water quality data over a longer time period is necessary to understand potential impacts to the OAC. The Ausable Bayfield Conservation Authority and the Pinery, along with volunteers from local neighborhoods continue to collect water samples in 2007.
The following eight indicators are tested for:
Total Dissolved Phosphorus
Total Kjeldahl Nitrogen
Total Suspended Solids
Definitions of Parameters
E. coli are a type of fecal coliform bacteria commonly found in human and animal waste. Its presence in water is a strong indication of recent sewage or animal waste contamination and also indicates the potential for the water to have other disease causing organisms.
Phosphorus (Total Phosphorus and Total Dissolved Phosphorus)
Total phosphorus (TP) includes dissolved phosphorus and forms bound to organic and inorganic material in water. Total phosphorus is an element that enhances plant growth and contributes to excess algae and low oxygen in streams and lakes. In many fresh water aquatic systems, phosphorus is the nutrient limiting primary production (plant growth). When phosphorus is added, the first response is increased primary productivity. Although, this may be an aesthetic concern, increased productivity may be beneficial to aquatic life. Excessive enrichment may lead to detrimental effects, such as a decline in water oxygen concentrations upon the decay of the aquatic plants.
Nitrate, Nitrite & Ammonia
Nitrate is the primary source of nitrogen for aquatic plants. All forms of inorganic nitrogen (nitrite and ammonia) have the potential to undergo nitrification to nitrate. In well-oxygenated systems, increasing concentrations of inorganic nitrogen increase the risk of algal blooms and eutrophication. Furthermore, nitrate may also be directly toxic to aquatic organisms. Elevated nitrate concentrations are considered to contribute to eutrophication and its undesirable effects, such as algae and macrophyte blooms, shortened food chains, and changes in the aquatic community.
Total Kjeldahl Nitrogen (TKN)
The sum of organic nitrogen and ammonia in a water body. Measured in milligrams per liter (mg/L). High measurements of TKN typically results from sewage and manure discharges to water bodies.
Total suspended solids (TSS)
Turbidity and TSS are different parameters that provide complementary information about water quality. Turbidity is a measurement based on optical properties that quantifies the amount of light that is scattered and absorbed rather than transmitted. Total suspended solids (TSS) is a main component of turbidity, however, it is a measure of material suspended in the water column such as microorganisms, phytoplankton, detritus, clay and other mineral substances. High TSS levels could have a limiting impact on fish communities, especially sensitive fish species that require clear water.
Sampling Results from the 2006 Season
The following chart shows the results of sampling from March 2006 to November 2006 in the OAC at one location in Pinery Provincial Park.
OAC Water Quality Data
OAC Water Quality Data
ND= not detected
The water quality sampling location was directly upstream, mid channel of the Pinery dam.
Water Quality in the OAC
Average total phosphorus, nitrate and E. coli results between the OAC and the rest of the Ausable River/Bayfield River watersheds (this data was taken from the ABCA’s Watershed Report Card document) were compared. Total phosphorus, nitrate and E. coli were chosen because of phosphorus and nitrate’s connection to increased plant growth/algal blooms (which is apparent in the channel) and E. coli’s connection to septic/sewage indication.
The data comparison showed (Figures 1, 2 & 3) that the levels of these parameters are significantly lower in the OAC compared to the rest of our watershed area. This was not surprising given the OAC is a closed and isolated system to influences that the rest of the watershed would be receiving, for example agricultural inputs. There is a lot of vegetation present in the OAC, but water clarity and lack of flow could also be providing the favorable conditions for certain types of vegetation to grow. Some of the vegetation, such as Chara, doesn’t like a lot of nutrient input which could explain its abundance in the OAC upstream of the Pinery dam. We will need to continue monitoring the water quality to notice increases or decreases in the parameters, or make conclusions on what is happening.
The water quality sampling program in the OAC uses existing resources to provide critical information about the state of the OAC. Detailed water quality information is required to help guide management decisions of this unique ecosystem.