Flood Plain Study
The South Saskatchewan River flood plain has been a controversial area for development within Corman Park for many years. In May 2016, R.M. Administration recommended that Council undertake a two-dimensional (2D) hydraulic modelling and mapping study of the flood plain; a map of the study area can be found HERE. At the August 21, 2017 Council meeting a motion was passed that the R.M. will pay 100% of the costs of the study under the condition that 50% will be reimbursed through grant funds.
The R.M. has successfully applied for funding under the National Disaster Mitigation Program – Stream 2: Flood Mapping, administered by Public Safety Canada. The federal government will pay for 50% of the project costs and the R.M. will be responsible for the other 50%. The provincial Ministry of Government Relations will act as a conduit for the monies to be transferred to the R.M. due to their funding requirement structure with Public Safety Canada. A Request for Proposals (RFP) for the preparation of the study was posted on SaskTenders on January 16, 2018. The deadline for receipt of proposals was February 12, 2018; thirteen (13) proposals were received. On April 16, 2018 Barr Engineering was selected by R.M. Council as the consultant for the study. In order to obtain federal funding, all required reporting must be submitted by March 31, 2019. Barr Engineering is proposing to have the project completed by the end of 2018 which allows ample time for final reporting in addition leaving a buffer in case of any schedule slippage (for example the river survey is delayed due to spring conditions).
The R.M. will form a Technical Committee comprising of R.M. Administration, Water Security Agency and Community Planning representatives and other technical resources as appropriate. The consultant is expected, at a minimum, to meet in person with the Technical Committee at the commencement of the study and provide in person summary presentations to the Technical Committee, R.M. Committees and/or Council at the conclusion of the study. Regular updates to R.M. Planning Committee will be provided by the Planning Department throughout the course of the study. It is also intended to communicate with area residents through mail out and website updates as to the intent and status of the project. Some landowner access may be required during data collection and the R.M. will assist in coordinating with the consultant.
The phased approach to the development of the study will be implemented as follows:
Phase 1: Data Confirmation & Field Survey (April – June 2018)
This phase includes review of available background information including statutory documents, data and related studies prior to development of the 2D model. Following a review of the data to identify any gaps, a field survey would be completed to complete the data acquisition. This includes a hydrographic survey of the river as well as ground survey of culverts and other infrastructure.
Phase 2: Hydraulic Modelling & Assessment (May – September 2018)
During this phase of the project the terrain dataset would be developed, the model parameters would be defined, and model calibration, validation and sensitivity analysis would occur. This step is crucial to ensuring a successful outcome for the study. Following these steps the model would be ran to stimulate the regulatory flood event (1:500) in addition to three smaller events (1:50, 1:100, and 1:200). The effect of full residential development (i.e. 5 per ¼) would also be considered as part of a modelling exercise for the 1:500.
Phase 3: Mapping Support & Flood Mapping Report (July – December 2018)
These final phases of the study involve completing GIS maps illustrating the flood plain, floodway and flood fringe. A written report will also be completed by the consultant to document data collection, the modelling assessment, flood mapping methodology and development of the flood plain maps.