Keewahdin Elementary Parking Lot Addition
Port Huron Area School District – Fort Gratiot, Michigan
The Port Huron Area School District contracted with BMJ to help them find a solution to the issues that had plagued Keewahdin Elementary school for many years – parking and congestion before and after school.
A greater percentage of the student population at the school is dropped off and picked up every day than is typical throughout the district. Combined with an already undersized parking lot with poor circulation, this created a significant problem with parking and congestion. Events held at the school resulted in vehicles being parked in grass areas around the parking lot and along Lakeshore Road, creating a chaotic and potentially unsafe condition for those using the facility and drivers on Lakeshore Road.
To solve these issues, it was necessary to design a much larger parking lot to provide the capacity needed at peak times, as well as providing clear circulation patterns for more efficient drop-offs and pick-ups.
BMJ’s design team created a layout that provided those improvements. However, because of the much larger parking lot, storm drainage became an issue. The existing small parking areas had no storm drainage outlet from the site, taking advantage of the sandy soils around the site to infiltrate storm runoff into the ground. The new parking lot, having a significantly larger impervious surface, would generate much more runoff than the existing lot.
BMJ’s design team, in cooperation with the St. Clair County Drain Commissioner’s office, found a low-impact solution that would address the issue and provide additional security in large storm events.
The new system was designed, like the old one, to take advantage of the sandy soils under the site. A drain field, similar to a septic field, was installed underneath the new parking lot to distribute the stormwater over the sand subgrade for infiltration. The drainage piping was laid in a large stone area that also provides detention storage at times where water is entering faster than it infiltrates into the ground.
As an additional measure of security, the school district obtained an easement from the adjacent property owner to construct an overflow to the county drain near the site. In large storm event that cause the detention storage to fill up, the excess drainage will be discharged to the drain rather than backing up in the parking lot.
