Master Stormwater Management Plan
The County of Vermilion River is located adjacent to the Alberta-Saskatchewan border, west of the City of Lloydminster. The extent of the county is from the Battle River in the south to north of the North Saskatchewan River in the north and from the provincial boundary, the fourth meridian in the east to Range 7 in the west. The Vermilion River runs through the middle of the western half of the County to it's confluence with the North Saskatchewan River.
Except for the areas adjacent to the main water courses; there is very pour natural surface drainage. Most of the land in the County drains to local intermittent depressions or potholes. In the semiarid climate, evaporation exceeds precipitation and the water from these potholes is returned to the atmosphere without overflowing. Erosion has not developed natural drainage courses to drain the intermittent depression and most of the County lands do not really contribute to the flow of the main watercourses. The surface area of the potholes varies greatly from year to year. In dry periods many of the potholes completely disappear and in wet period they can expand over large areas.
The traditional dominant economic activity in the County was agriculture which accommodated the natural hydrologic regime with minor difficulty. In the region around Lloydminster the County has experienced substantial growth of industrial and residential development . This has resulted in significant changes in the interaction between the developments and the hydrologic regime. The developments include buildings and other facilities that cannot accommodate flooding. The developments change the hydrologic regime due to decreased infiltration and constructed drainage works which increase the runoff potential. The developed areas tend to experience spring runoff before the rural areas which increases the duration of the runoff period and usually decreases the magnitude of the spring
peak discharge. The frequency of runoff from storm events also increases as rural areas are developed.
Recent higher than normal precipitation has resulted in greater flooding in the developed areas and downstream of developments than was anticipated when the existing projects were implemented. The County recognized that a more comprehensive planning process will be needed to improve drainage of existing projects and to ensure that future developments do not compound the drainage issues.
The Master Stormwater Management Plan will include:
- Development of a stormwater model (utilizing 1:100 year storm event conditions) including assessment and recommendations for specified priority locations. The locations were further identified to be in either Area 1 or Area 2. Area 1 is the area in the County surrounding the City of Lloydminster which has and is expected to receive the majority of development activity, and is the focus for the development of the stormwater model. The remaining area of the County is designated as Area 2. Though the stormwater model is limited to Area 1, the Stormwater Master Plan will promote best management practices for stormwater in the entire County
- A review and characterization fo the basins and drainage features defined in Area 1. Assessment was also made on existing and proposed developments within this area to identify stormwater issues and develop concepts to remediate potential impacts. The drainage basins and flow directions were also documented at specific locations identified by the County in Area 2.
- A review of requirements of County of Vermilion River Bylaw PD009 Storm Water Management in the County of Vermilion River Policy and Operations Manual.
Documents: (links to external document management site)
Master Stormwater Management Plan Draft
Master Stormwater Management Plan Technical Report Draft