Bow River Basin

The Alberta government has a five-year agreement with TransAlta to modify operations at several TransAlta facilities to help protect communities along the Bow River against the impacts of both floods and drought.

Modified Operations Agreement with TransAlta

The Alberta government is committed to ensuring our province is prepared for the potential of future flooding and drought. Leveraging existing TransAlta infrastructure is an effective option to help protect communities along the Bow River.

Terms of the Agreement

  • Compensation paid to TransAlta is $5.5 million per year
  • Five-year agreement beginning in May 2016
  • Modified operations period at Ghost Reservoir is from May 16 to July 7, primarily for flood mitigation purposes
  • Year-round modified operations at Barrier Lake, Upper Kananaskis Lake, and Lower Kananaskis Lake, primarily for drought mitigation purposes

Frequently Asked Questions - Updated May 1, 2017

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Flood Storage

How much flood storage is provided through the new agreement with TransAlta?

Up to 65 million cubic metres of storage will be available at Ghost Reservoir for flood mitigation purposes. Approximately 10 million cubic metres may be available at the Kananaskis-area reservoirs further upstream for drought mitigation. The amount of storage available will vary each year based on prevailing conditions.

Will flood storage prevent flooding?

Flood storage can prevent small floods, which are most common. In the case of an extreme event (such as the flood experienced in 2013), storage will not absolutely prevent flooding but can reduce the impact.

How does flood storage work?

In order to store anticipated flood water, the existing water levels in reservoirs must first be reduced. The flood water that is subsequently stored is then released in controlled amounts. Less water travels downstream at a time. Just as importantly, the action also delays peak flows downstream. This is critical when evacuating major population centers.

What are the implications for Calgary and other Bow River Communities?

The ability to regulate high flows on the Bow River will help reduce the impact of major floods and eliminate smaller floods in communities along the watershed, including Calgary. During times of drought, water stored in upstream reservoirs (Kananaskis System) can be released into the Bow River to maintain environmental flows, for municipal drinking use and for use in irrigation, thereby helping to protect valuable crops.

What other opportunities are there to store water in southern Alberta?

Recent grant approvals through the Watershed Resiliency and Restoration Program will see over 500 hectares of wetlands created or restored, mostly in southern Alberta. Wetlands are very effective for improving both flood and drought resiliency.

How will these reservoirs be managed if we are facing drought conditions?

The new agreement with TransAlta includes the Kananaskis sub-basin, which provides the Province with potentially more storage options to supplement flows in the Bow River during dry years. This is a key element in adapting to weather extremes brought on by climate change.

Initial reservoir target elevations prior to each operating season will be based on the provincial Water Supply Outlook, snowpack and soil moisture conditions, and prevailing weather patterns. In wet cycles, reservoir levels will be kept lower to facilitate potential flood storage. During dry cycles, target elevations will be kept higher to offset potential water shortage conditions later in the season, but still allow the reservoir to be lowered up to five days prior to a flood event. Seasonal operational targets will be posted under Forecaster’s Comments at:

What are 2017 reservoir operations looking like?

Government is working closely with TransAlta to assess what elevations reservoirs should be set at going into this coming operating reason. Looking at current snowpack conditions in the mountains, baseline river flows and the Provincial Water Supply Outlook conditions are looking to be average to above average coming into this summer.

Much above average snow in the mountains means storm events could generate higher flood flows but also means a higher likelihood of being able to fill the reservoir later in the summer. For these reasons, in 2017 the Ghost Reservoir level will likely be set lower than 2016 levels.

Up-to-date information on all reservoir elevations, river flows and proposed forecasted operations will be posted on the Alberta Rivers App, available for Apple and Android devices.

TransAlta Agreement Details

What is included in the agreement between TransAlta and the Province of Alberta?

Flood Management: The agreement allows the Province to set elevations on the Ghost Reservoir during the period of May 16 to July 7 until 2021, which is typically the highest storm risk period of the year. By keeping the reservoir lower during this period there is more space to store flood events thereby lowering peak flows downstream of the dam or, at the very least, delaying those peaks.

Drought Management: The agreement includes the ability of the government to have TransAlta store water in the Kananaskis system to be used in periods of low flows in the Bow River. This part of the agreement is year-round for the duration of the agreement.

Why is the government paying TransAlta to modify operations at some of their facilities?

As per the agreement, reservoir levels at four TransAlta facilities will now be set by the Province based on flood or drought mitigation needs. Compensation paid to TransAlta is intended to offset the estimated commercial loss TransAlta will incur due to modified operations at the four facilities included in the agreement. These reservoirs are designed and operated to produce electricity. The lower the water level, the less electricity TransAlta is able to produce.

Did the government consult with impacted residents?

Yes, we met with impacted residents, business owners, recreational users, and other key stakeholders in 2015 and 2016 to explain the agreement and to identify and discuss issues related to low water levels at Ghost Reservoir. We held numerous engagement sessions during 2016’s modified operations period and will continue to provide information to stakeholder groups through the life of the agreement.

How does the agreement with TransAlta relate to the mandate of the Bow River Working Group?

The Bow River Working Group, jointly chaired by the Province and the City of Calgary, is assessing flood and drought mitigation options for the Bow River from the Banff National Park boundary through to Medicine Hat. This includes a combination of new structural projects and modified operations at TransAlta facilities. Because of the amount of storage required to meet flood and drought mitigation goals, the use of TransAlta infrastructure will almost certainly be a significant part of the final mitigation solution for the Bow River.

Wells and Water Supply Management

What steps have the province taken to resolve the issues some residents near Ghost Reservoir are having with their wells?

A study was completed by an independent engineering consultant on behalf of the department to determine how domestic wells may be impacted at different reservoir elevations. The study is currently being reviewed and will be made public later this spring.

In 2016, Alberta Environment and Parks was not made aware of any domestic water wells within the village that required supplemental water supply. In 2015, a total of four wells were affected and the department provided a temporary water supply to those residents until their wells were restored. If required, we will do the same this year.

Will the aquifer study include actual studies of all the residents’ wells? Changes in water quality and pressure were noted last year in many of the resident wells.

The department’s engineering consultant contacted all licensed water well owners within the Village in the summer of 2016 and requested completion of a detailed questionnaire to identify wells that have experienced issues in the past. The consultant also visited several private wells for inspection and gathering of technical information including water levels and pump test results. The study also utilized existing information for licensed wells within the Ghost Lake Village and published geological information for this area as key inputs for their analysis.

What happens if residents in the summer village have repeated issues with their wells? What will the government do to assist covering costs for drilling another well?

We have not heard of any well issues in Ghost Lake Village in 2016. If there are unreported issues we would like to know about them as soon as possible so that an assessment of the affected well can be arranged. Residents can contact the department’s Information Centre:

A rural resident (outside of Ghost Lake Village) stated her wells were severely impacted. When will this issue be addressed?

The study will provide department officials with information on the general groundwater characteristics around the reservoir and allow a more informed discussion with residents outside of Ghost Lake Village who claim their wells are affected by reservoir levels. Alberta Environment and Parks is working directly with this resident to assess her concerns.

What about the wells of other neighbours in the area including the Stoney Nakoda First Nation? Have they been impacted as well?

To date, Alberta Environment and Parks has not received any additional concerns regarding wells.

What is the status of emergency water supply at Ghost Lake Summer Village?

Alberta Environment and Parks is working with the Ghost Lake Village administration to ensure that if residents experience water issues directly linked to reservoir operations, they will be supplied with supplementary water. In 2016, this involved trucking and piping water to affected residents as required.

It was noted that a pump and hoses had been delivered to Ghost Lake Village for fire protection in 2016. What about this year?

The Village and rural municipality are responsible for fire emergency response. Alberta Environment and Parks will supply the village with a large mobile pump (and appropriate training) to aid the Village in fire suppression, should that be required. The pump that Alberta Environment and Parks supplied is only for supplemental supply to support and assist with the response planning.

In 2017, this will be in place as of May 15th.

Improved access to ramps at the Marina and Ghost Lake Village for the RCMP and Fire and Safety have been promised but nothing is in place. When will something be put in place?

Alberta Environment and Parks is working with Parks Division and the Village to extend boat launch access to the reservoir. Currently the department is seeking approvals to extend Parks’ boat launch. It is anticipated this work will proceed in the spring of 2018.

Other Local Impacts

Will the government compensate landowners and businesses around Ghost Reservoir for the impacts caused by lower water levels at Ghost Reservoir?

Lower water levels at Ghost Reservoir during the period of this agreement are still within the operating limits of TransAlta’s water licence. Government will undertake an assessment of water supply issues in the Summer Village of Ghost Lake and work with area residents and businesses to find solutions to issues associated with lower water levels. To date, solutions include things like installing a temporary water supply for the summer village and extending the boat launch.

How will lack of access to a water supply for fire prevention affect residents’ insurance? This should not be at their expense and should be covered by the government. Is this a possibility?

Ghost Lake Village and the rural municipality are responsible for fire suppression services. Alberta Environment and Parks will supply the Village with a large mobile pump (and appropriate training) to aid the Village in fire suppression. Residents who have concerns regarding insurance should contact their insurance provider.

Taxes have not decreased but in fact increased over the last few years. Why has there been no compensation or lowering of taxes for the residents?

Residents are reminded that Ghost Lake Reservoir is a "reservoir" and will fluctuate over a broad range of elevations. Elevations during May 2016 were not unprecedented and closer to historical norms. The reservoir is being operated within its licensed range and has, historically, been at these levels.

Issues regarding municipal taxes should be discussed with the municipality. The province has not compensated other residents near flood mitigation projects. Some flood mitigation projects have a land acquisition requirement in order to proceed. Acquiring land to build a project is not the same as compensating residents for minor impacts.

Has the Marina been consulted and compensated for loss of revenue? When will government consult and provide some compensation for modified operations?

Alberta Environment and Parks met with impacted residents, business owners, recreational users, and other key stakeholders in 2016 to identify and address issues related to low water levels at Ghost Reservoir. The department will continue to provide information throughout the term of the agreement with TransAlta.

More Information

Have a question about the modified operations agreement between the Alberta government and TransAlta? Contact the Information Centre:


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Updated: May 1, 2017