Rainy and Namakan Lakes Rule Curves Review

Rainy and Namakan Lakes Rule Curves Review

Study Strategy Comments by the Rainy Lake Property Owners Association (RLPOA)

The Rainy Lake Property Owners Association (RLPOA) thanks the Rule Curve Study Board for establishing an informative dialogue with our organization and Dr. Jeffrey Kantor, and considering his work on Adaptive Rule Curves which coordinates levels and flows for Rainy and Namakan Lakes. We hope this sharing of scientific analysis and modeling will be beneficial to the 2000 Rule Curve Review and result in a modern, data driven control strategy for Rainy and Namakan Lakes.

Objective and Scope.

The RLPOA is concerned that the proposed Study Strategy for the Rule Curves review has narrowed the Objective and Scope to the extent it may miss important opportunities to develop effective long term solutions to controlling water levels in the Rainy and Namakan watershed. The rule curve and established operating procedures will be in effect for the foreseeable future. By restricting the options available to this study, it would be unfortunate if the results were a minor tweak to the rule curve rather than initiating adaptive management techniques for benefit of lake residents, users, and health of the overall watershed.

As a result of this narrow Objective and Scope in the Directive and Terms of Reference, the primary evaluation of the 2000 Rule Curve will be a comparison against the 1970 Rule Curve and State of Nature. SON is a hypothetical basin configuration which is an approximation of actual pre-dam conditions and a condition which can never be measured or duplicated.

Seine River and Other Dams

The proposed Study Strategy will not consider coordination or regulation with other dams in the watershed although the scope includes Littlefork, Bigfork, as well as water upstream from International Falls. The original directive for the 2000 Rule Curve review did not define the scope so narrowly. The Seine River system accounts for approximately 14% of the controllable inflow to Rainy Lake. While we understand it is not included in the scope, it is extremely important that its effect on management should be incorporated as part of the Study Strategy. If necessary, the IJC should take action to coordinate management of the Seine River as part of its mandate to manage the watershed on the border of the U.S. and Canada.

There may be significant peaking and ponding that takes place in the Seine River System. RLPOA has asked for historical flow data from H2O Power. That data was not made available based on the claim that release would reveal proprietary operating information. The position of the RLPOA is that reliable data from the Seine River system should be available for study and management of Rainy Lake as part of the IJC’s mandate for management of the international watershed.

Ranier and Upper Rainy River

Flow restrictions at the Ranier railroad bridge and on Upper Rainy River have been evident for at least 50 years. It was statedduring our meeting on March 8th that possible adjustments to these flow restrictions would not be included in the scope of study for several reasons, among them time constraints for this study, lack of obvious funding sources for any changes that may be proposed, and a complex array of stakeholder issues.

However, the proposed SON scenario for the Study Strategy assumes pre-dam conveyance performance characteristics that would not be very different from today. To the best of our knowledge, no one really knows how much of a natural restriction existed before the Rail Bridge and embankment. The historical high water marks left on the shorelines provide some performance indicators from the past. In our view, it is essential that the Rule Curve Study recommend further study of the effects of the restrictions in Upper Rainy River and possible solutions.

Real-Time Regulation

A real-time regulation approach should be included within the scope of study and there should be a way to do it without a full time staff. Lake level should be adjusted based on actual rainfall rather than waiting until the water shows up as a rise in lake level, causing a significant delay in reaction time.

To this end, the Study Strategy should include a clear, measurable statement of the purpose and meaning of rule curves for this watershed. The current rule curves appear to be an ‘intent’ meaning it is the intention of the IJC that dam operators manage lake levels to within the rule curves. Too often since 2000, this intent has proven to be an infeasible goal. In order to provide a sound basis for lake level control, the rule curves need to go beyond ‘intent’ and link to performance measures that can be validated by hydrological models, and monitored over time. This is especially critical as we enter a period with increasing climate change, earlier ice outs, and more variable precipitation patterns.

In the past, timely decisions between advising engineers, water levels committee and dam keepers have involuntarily contributed to high water events on Rainy Lake. This was caused by not making decisions in a timely manner. A well managed predictive regulation approach with real time decisions should be implemented.

Shared Vision Planning (SVP)

One of our concerns is that the value for the Performance Indicators (PI’s) for the IERM will be arbitrarily assigned and “…will form the basis for comparison of different alternatives under the Shared Vision Planning (SVP) approach.” In cases where there are no existing studies, it appears analysts will need to make arbitrary decisions. Our concern is that this leads to a non-transparent process where the relative weights assigned to competing interests will be an analyst’s choice.

Data from studies and assumptions generated during the Weight of Evidence exercise could influence WOE which will slant results of the IERM. An example of this is the effect of conservation efforts related to fisheries in both Rainy and Namakan Lakes. Commercial fishing of walleye was eliminated in the early 1980’s and local conservation began with stocking and a mandatory Catch and Release program. All of the above harvest reduction strategies have improved the health of fisheries in Rainy Lake and Namakan. This may have an impact on results used in the WOE which will influence IERM modeled. How will this potential conflict of data and results be mitigated?

The 1970 model used in this analysis suggests that dam keepers targeted the middle of the rule curve. However, at that time there was no directive and the dam keepers operated within the curve and targeted different levels at their own discretion. This assumption made by the modeler may generate conflicts between the 1970 and 2000 models.

As stated on page 17 of the proposed Study Plan, “the coding of the regulation alternatives into the SVM will reflect the operational constraints of the management system, including imperfect inflow forecasts and lag times for executing flow changes at the dams.” While we agree the SVM ought to be based on realistic data and operational constraints, the rule curve order should specify actions to correct the operational and hydrological constraints of the management system, correct inflow forecasts, coordinate operation among dam operators in the watershed, and reduce the lag times for executing flow changes at the dam.

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