Water Level Information
Big Basswood Dam
August 6, 2013: Below is an email update from Ray Lipinski of the MNR, who manages our dam at Harris Creek.
I have been off for a while so apologies for the delay in responding.
The target operating level for Basswood Lake is 208.295 mCGD (metres Canadian Geodetic Datum = metres above sea level) during the summer and 208.165 mCGD during the winter months. The target level is achieved through operation of one or both of the knife gates. The lower winter level reduces the potential for ice damage usually caused by high water levels in the spring, and flooding of shoreline and downstream property damage during the spring freshet. The fall draw down normally occurs by early October just prior to lake trout spawning. The water levels were determined based on public input and consideration of ecological requirements. The dam is normally visited approximately every two weeks, with the frequency of inspection and/or operation increasing depending on conditions. During freshet or high flow conditions the dam is often checked on a daily basis. The Emergency Preparedness Plan level is 208.50 mCGD. This level is based on dam design and watershed characteristics and is the level at which emergency action is taken to ensure dam and public safety measures are implemented.
The target operating levels corresponded with values of 0.75 m (summer) and 0.62 m (winter) on the gauge which used to be located on the dam, but has been destroyed by ice. A new gauge will be installed on the dam.
The Basswood Lake Dam is operated primarily with the intent of maintaining the water level near the target level. However, consideration is also given to Bright Lake water levels as well as water quality. For example this past spring and early summer the maximum outflow was not discharged from the Basswood Lake Dam, due to very high levels in Bright Lake. The levels on Bright Lake were causing significantly greater problems than the somewhat high levels on Basswood Lake. Bright Lake was experiencing significant flooding issues. The region experienced unusually high flows during late spring and early summer for an unusually long period of time. High flows in the Mississagi River impeded the ability of Bright Lake to drain, compounding the problem of high water levels. A second recent example was during the late summer of 2012 when approximately four inches of water was discharged from Basswood Lake over about two weeks to help mitigate the onset of a blue-green algae bloom on Bright Lake. We recognise that the supply of Basswood Lake water to Bright Lake is only part of the approach needed to deal with the water quality and water level problems, but it is an important component. Bright Lake is not regulated otherwise, so the levels will fluctuate naturally, depending on the amount of inflow and outflow. The Bright Lake Association has been working hard for several years to understand and also address the water quality issues, and is making progress toward improvements.
If you have any questions please give me a call or e-mail.
Resource Management Technician
Ontario Ministry of Natural Resources
Blind River Area Office
PO Box 190
Blind River, ON P0R 1B0
Tel: (705) 356-3008
Fax: (705) 356-7441
Lake Water Level InformationSeptember 28, 2012: Many of our lake residents have expressed concern about the low lake levels late in the summer. Below is a response from Ray Lipinski of the MNR, who manages our dam at Harris Creek..
MNR allowed Basswood Lake to go down several inches beginning in the last week of August mainly at the request of the Bright Lake cottager's association. The Bolton River outflow from Bright Lake was virtually stagnant. The Bright Lake people had expressed serious concerns over algae blooms forming on Bright Lake. The slight increase in flow may have helped to avert a more serious problem with blue green algae in Bright Lake. Blue green algae and related toxins are a huge problem for property owners on an affected lake. The lake water cannot be used for drinking, showering, cooking, or swimming. You can not even let your dog swim in the water when a blue green algae bloom occurs. Often the warnings associated with presence of blue green algae remains in place for months or seasons.
The property owners on Big Basswood have high expectations for stable lake levels during the summer, which does occur, most of the time. As I indicated on the phone, it is ecologically unhealthy for a water body to not experience a normal range of water level fluctuations, which for a lake the size of Basswood would be easily 0.6 m, or about two feet or more. However, we manage the lake level primarily for the benefit of the property owners, who want stable water levels, and the lake typically is maintained within about a 6 inch summer range.
The people on Bright Lake believe that Basswood Lake gets the priority for water, and that MNR manages the lake solely for their benefit with little or no consideration for Bright Lake. MNR must manage resources for all users, and not solely for the benefit of one group. The levels on Bright Lake are controlled by natural factors, but are also significantly affected by beaver dams on the Bolton River. If there is little or no through flow of water in Bright Lake, this will contribute to heating of the water body, reduction of dissolved oxygen, and accelerated growth of algae. We understand that Bright Lake has no level control structure (dam) at the outlet, so water provided to the lake from Basswood will not necessarily raise the lake level, but it will help move cool well oxygenated water through the lake. If Bright Lake is higher than normal due to beaver dams (which it has been), it only exasperates the problem of through flow in the lake. The lake still needs water moving through it to prevent stagnation and the problems resulting from that.
For the majority of the summer there was very little discharge from the Basswood Lake dam, keeping Basswood at normal levels, while most area lakes were significantly low. At the same time water was being conserved in Basswood Lake, it was not providing cool, well oxygenated water moving into and through Bright Lake. This situation is a contributing factor to formation of algal blooms in Bright Lake. The Basswood Lake dam was opened a small amount beginning in the last week of August. It was believed that this action would allow Basswood property owners to share a small amount of the pain and some water with Bright Lake, as the entire region experienced drought conditions this past summer. It was also expected that this would result in relative minor inconveniences to Basswood Lake property owners. The discharge from the Basswood dam was reduced in the first week of September, and almost completely stopped in the second week of September, and has been almost completely stopped since then.
The Bright Lake Association has been actively working to address the water quality problems associated with Bright Lake. They have done a considerable amount of research and have developed a good scientific understanding of the processes occurring in Bright Lake. They also understand that the amount and timing of water from Basswood Lake is only one factor of several that affect water quality in Bright Lake. They have done some mitigative work to control agricultural runoff in Pickerel Creek, and are pursuing other courses of action as well.
The perception of many property owners is that the change in water level is larger than it actually is. We record the level of Basswood Lake on a regular basis. All area lakes have been at extremely low levels for most of the summer. Most people noted the extremely low levels on the Mississagi River over the past summer. This is mainly because the inflows to Rocky Island Lake and Aubrey Lake were a very small fraction of the normal long term average. This is because we have been experiencing drought conditions. We have current hydrology records for flow stations on local rivers such as the Aubinadong, Root River and Little White River. These unregulated rivers have had near record low flows this past summer. In reality the property owners on Basswood Lake have been largely isolated from the effects of a drought such as this, and as a consequence may have little empathy for the needs of downstream property owners.
The Basswood Lake levels for the last few months are below (metres above sea level).
To translate this, the normal summer level is two to four inches below the wingwall. The present level is approximately 7 inches below the wingwall.
Although no one can predict with any certainty, the frequency of dry or very dry summers may be increasing due to climate change. This may become a more significant consideration for water management in the future.
I hope this information has been helpful. If you have additional questions please give me a call.
Operations Specialist - Renewable Energy
Ontario Ministry of Natural Resources
PO Box 190
Blind River, ON P0R 1B0
Tel: (705) 356-3008