The Sunchild First Nation has reserve lands located approximately 60 kilometres northwest of Rocky Mountain House, Alberta. The Nation Land consists of approximately 12,800 acres of land on both sides of the Baptiste River.
Over a period of some years, intense rainfall events have occurred, which has resulted in overland flooding and damage to road and infrastructure assets. Portions of the roadway lie within the floodplain of the Baptiste River and river flooding has had a compounding effect on the ability of the current culvert structures to pass water. Rainfall events such as that during April of 2017 as well as more historical events, saw water levels at the culvert crossings at the same level or even above of the roadway in certain cases based on anecdotal reports.
Addressing the recommendations outlined in a Community Drainage Study Report, the Sunchild First Nation Project Management Team selected Allnorth to provide engineering design services for the replacement of three bridge size culverts on the main access road to the Sunchild First Nation. Several structure options were evaluated for the upgrades to Crossing #1 based on cost, geotechnical conditions, availability of local materials, ability for First Nation labour force and long-term maintenance requirements for the Nation. A 8.271m span x 3.075m rise x 27.508m long Super Core Geosynthetic Reinforced Soil (GRS) arch structure was ultimately selected and installed by a local contractor.
Project challenges included limited instream construction period governed by Restricted Activity Period (RAP), water management, coordination for the relocation of multiple gas, phone and fibre optic lines buried in existing road, and inclement weather; however, teamwork between Allnorth, Sunchild First Nation and the Contractor resulted in completion of a successful project.
- Hydrotechnical review of drainage study recommendations
- Environmental assessment & permitting
- Geotechnical investigation
- Remedial options analysis report
- Preliminary crossing design
- Detailed crossings design
- Tender package preparation
- Contract management
- Construction management and field reviews
- Final Details Report
Sunchild First Nation near Rocky Mountain House, AB