Okotoks Stormwater Master Plan

Okotoks, AB

The Town of Okotoks has been experiencing a high level of growth and expansion, as well as some recent flooding issues. ISL was commissioned to develop a comprehensive Stormwater Management Master Plan and Flood Mitigation Plan.

Project Goals

The project was undertaken to define the existing stormwater system capacity, to catalogue possible upgrades and to review the system's operational strategies. The study was also intended to define future drainage planning goals in the undeveloped areas of the Town and create a single point of reference for stormwater planning.

LID Integration

The Town of Okotoks wanted the Master Plan to include the integration of low impact development stormwater management features and other sustainable solutions. To meet this criteria, the Master Plan ensures that sustainable stormwater infrastructure will be integrated with natural ecosystems and resident-friendly park spaces to optimize water quality prior to discharge to Sheep River.


For each possible upgrading scenario, improved system performance needed to be demonstrable, so ISL used state-of-the-art hydrodynamic modelling software (XP-SWMM) to individually evaluate and model each upgrading scenario.

Study Results

ISL compiled and reviewed existing reports and drainage system information, then used this information to conduct an analysis of the capacity of the existing stormwater infrastructure to identify the flooding issues. We also completed an assessment of the required upgrades and prepared preliminary cost estimates.

Master Plan

In November 2014, the Town was given operational strategies to prevent property damage in the event of flooding and guiding policies for sustainable and low impact development measures for retrofit and future incorporation.

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