Water Monitoring Program at Lac Le Jeune
Following the Annual General Meeting of the Lac Le Jeune Conservation Association, held on September 17, 2011, a group of concerned Lac Le Jeune residents met at the home of David and Kathy Wyse on September 29th. The purpose of the meeting was to discuss the potential impact of the proposed development above the Little Lake on the water quality we all rely on. The meeting was attended by permanent residents from all around the lake, including the Big Lake, the Little Lake, Ridgemont and Lookout Road. The result of the meeting was that a working group was formed made up of Bob Brown, Hugh Burton, Jim Phillips and David Wyse. The purpose of the working group was three fold:
- 1. To study the potential impact of further development at Lac Le Jeune on the quality and supply of water for current and future residents.
- 2. To become familiar with the TNRD Lakeshore Development Guidelines.
- 3. To communicate information concerning development with Lac Le Jeune property owners and with appropriate government agencies.
The working group met a number of times in October and November to share and discuss information they were studying. The executive of the Lac Le Jeune Conservation Association was contacted about the work and purpose of the group and the working group was designated as a sub-committee for the Association whose mandate was the same as the purpose of the group.
On December 11th, a letter was sent to the TNRD outlining our concerns. (A copy of this letter can be seen on the Lac Le Jeune blog as well as on the bulletin board at the dump). Copies of the letter were sent to different departments within the Ministry of the Environment and to the Department of Fisheries and Oceans. We received a letter from the TNRD acknowledging receipt of our letter but no other responses for two months.
On February 29, 2012, we received an e-mail from Marg Sidney who is with the Water Quality Section of the Ministry of the Environment. In her e-mail to us, Marg indicated that Lac Le Jeune had been "on her radar" for some time and asked if there would be interest in beginning a water monitoring program for the lake(s). She also told us that before a water monitoring program could begin we would have to join the B. C. Lake Stewardship Society (BCLSS). The $40.00 group membership fee included a Secchi Disc worth $45.00 as well as insurance for volunteers involved in the lake monitoring. The executive of the LLJ Conservation Association approved membership in the BCLSS.
Our first meeting with Marg Sidney was held on April 4, 2012, when Marg described what was involved in a monitoring program. There are five levels of complexity involved in a lake monitoring program beginning with simply recording the temperature of the lake and doing a Secchi Disc reading. Levels two to five increase in complexity with the fifth level involving a full-blown assessment of activities that occur within the watershed that feeds into the lake that could have potential impact. Because of the interest and commitment shown by our group, Marg felt that we could begin monitoring at the third level which involves Ministry funding to pay for an analysis of the water samples we are providing to the Ministry of the Environment. Following this first meeting with Marg, Howie Mattfeld contacted our TNRD Area J representative to see if the TNRD would provide a grant to pay for the water meter needed to conduct the monitoring we are doing. After a bit of discussion back and forth with the TNRD, they agreed to purchase the required equipment and contributed close to $2000.00 to cover the cost.
Hats off to the grey haired group of volunteers who have committed to the monitoring program for the next three years (Bob Brown, Hugh Burton, John Krawchuk, Howie Mattfeld, Jeff Perry, Jim Phillips, Casey Sheridan and David Wyse). Hugh Burton has graciously agreed to coordinate this program. Anybody else interested in helping would be more than welcome (training provided!).
Over the past few years our resident anglers have reported a number of factors that have given rise to a heightened level of concern about the health of the lake. These include significant changes in:
- 1. The number and size of the hatches of those insects which our fish feed on.
- 2. An apparent increase in the size of the algae blooms that occur during the summer months.
- 3. Changes in the water chemistry as indicated by the water assays that are done on the water that is used by the subdivision, eg., increases in sodium and chlorine concentration from road salt.
- 4. An increase in the average size of the fish caught in a relatively short time span. This may seem to be contradictory given that the hatches appear to have diminished but this is not necessarily the case. (see below)
- 5. The first recorded winter kill of fish in Lac Le Jeune last winter.
The purpose of the water sampling is to attempt to determine what is causing these changes at an early enough stage so that appropriate corrective action can be taken.
The level three protocol aims at providing data on:
- 1. The clarity of the water which is done with a Secchi Disc. This is a simple, black and white patterned metal disc that is lowered into the water until the pattern disappears. The depth is accurately recorded and gives a general idea of how much light blocking material is in the water e.g., fine suspended sediment and varying densities of algae, bacteria and other organisms.
- 2. The level of nitrogen and phosphorous in the water. As with your garden, in the right proportion, these two promote regulated growth of phytoplankton (algae) and aquatic weeds, both of which are essential to the health of the aquatic system. In excess, however, they produce algae blooms and heavy, undesirable growth in aquatic vegetation. Since both nitrogen and phosphorous are major components of outflow from raw sewage and septic systems, monitoring their levels provides a good insight into how well our septic systems are working and how much danger there might be from run off from fertilizers used on lawns and gardens.
- 3. The concentration of oxygen dissolved in the water. This level is critical to the welfare of our fish as well as to all the other organisms in the aquatic systems that require oxygen to support life. Some of the oxygen in the water diffuses into it from the air at the surface and is mixed deeper by wind action. But the vast majority of it is obtained during the daylight hours from the weeds and phytoplankton through photosynthesis. You might imagine that the more weed and algae in the system, the better. Unfortunately, there are two reasons against this. First, when an excessive amount of nutrient is present, it promotes the growth of some species of blue green algae, which produce toxins. Second, algae and aquatic plants produce oxygen only during daylight hours when light levels are adequate. At night or when light levels fall below a critical point, plants respire in the same way we do, producing carbon dioxide. In the fall, light and temperature levels drop and the plants and algae stop producing oxygen and many of them die off. When they do, they begin to decay, a process which uses up oxygen. When lakes freeze over, oxygen can no longer diffuse into the water from the air and the decaying organic material depletes that which is left resulting in a fish winter kill. Plants and phytoplankton become detrimental when they are too abundant.
- 4. Chlorophyll a sampling is done as a means of estimating the quantity of algae in the water. A known volume of water is taken from three levels of the lake that light penetrates into and this volume is assayed for the presence of Chlorophyll a. The higher the reading, the greater the population of phytoplankton (algae).
- 5. It is important to know the temperature of the lake water throughout the full depth of water, so this is measured every meter at the deepest part of the lake. At each level, measurement is made of dissolved oxygen and specific conductivity. Water temperature relates to the water's ability to hold dissolved oxygen. Colder water can hold more oxygen than warm water. This reading relates to the viability of oxygen dependent organisms.
- 6. Finally, we measure the specific conductivity of the water. When present, certain minerals and salts increase the electrical conductivity of the water. In more common term it speaks to how hard or soft water is. When these materials are present in high concentrations the water is said to be hard. Our lake water is moderately hard, while water in Vancouver is soft. Well water her is very hard and would have high conductivity.
The fact that this was the first recorded fish winter kill indicates that the overall health of our lake is not good. The big lake is probably reasonably safe for the foreseeable future but the little lake, where the kill occurred, is already at a critical point. It is shallow, has a very high biomass index (lots of plants and phytoplankton), has a low flow rate, hence poor exchange for the volume of water present, and receives water from a populated water shed and from roads adjacent to it.
It is our hope and that of the Ministry personnel, that our three year study will allow us to counteract the adverse conditions that have led to the present state and to make educated, constructive and timely recommendations that will ensure continued viability of our beautiful and valuable resource.
~ Submitted by Hugh Burton and David Wyse
Marg Sidney, who is with the Water Quality Section of the Ministry of the Environment.
Marg instructs the water testing team.
David Wyse and Howie Mattfeld