At a Glance
The City of Shoreview, Minnesota needed to limit stormwater runoff into Lake Owasso to achieve compliance with the Federal Clean Water Act (CWA). Using a system of permeable articulating concrete blocks that capture water and filter out pollutants, Shoreview reduced runoff in line with CWA requirements.
The city of Shoreview, MN, (pop. 26,000) began renovating its streets in 1985 as part of the Street Renewal Program. Under the program, all streets were ordered to be brought up to modern standards for pavement, drainage, and public utility needs.
Throughout a project’s anticipated 40-year lifespan, drainage of stormwater was among the most prominent concerns with the existing neighborhood roads. Stormwater from either rain or snow tended to quickly run off the roads and drain into storm sewers along with trash or chemical pollutants it had picked up on the way. This polluted stormwater would often drain directly into neighboring Lake Owasso, leaving the city open to Clean Water Act compliance issues.
Because of these issues, the city sought to reduce stormwater and pollutant runoff in a way that protected Lake Owasso as well as ensured compliance with federal Clean Water Act regulations.
Shoreview, MN used/is using PaveDrain's P-ACB pavement to address this/these challenge(s).
After looking into green infrastructure solutions and trying pervious concrete, Shoreview discovered PaveDrain, a P-ACB (permeable articulating concrete block). Unlike traditional pavers, which utilize rock to fill the joints between them, PaveDrain utilizes an open joint concept to allow stormwater to quickly drain through the gaps and into the aggregate base then into the soil, thereby reducing runoff and recharging the aquifer. An added benefit is that by reducing the amount of stormwater on the pavement surface, less snow and ice can accumulate and Shoreview can reduce costly and environmentally destructive road salt.
Although P-ACB pavements had been traditionally limited for parking lots and parking lanes, Shoreview broke the mold by using them in 2014 to reconstruct streets in its Woodbridge neighborhood. The city’s decision was backed by research that PaveDrain P-ACB pavements was the most efficient way to satisfy city and watershed stormwater management requirements.
The city’s PaveDrain system works by allowing stormwater to drain through the open joints between the individual concrete blocks before encountering 18 inches of railroad ballast and a sand subgrade. These aggregate layers filter out and capture the pollutants, leaving the purified stormwater to absorb into the earth and recharge the aquifer. This infiltration of excess stormwater reduces runoff to Lake Owasso as well as reduces flooding occurrences on city streets. Between the infiltration capabilities of the pavement and the aggregate layers below, the system will only overflow after 2 days of continuous rain, falling at a rate of 1 inch per hour.
- As a result of the project, Shoreview reduced polluted stormwater runoff into neighboring Lake Owasso
- Shoreview reached compliance with the Federal Clean Water Act as well as actively helped recharge its aquifers through water infiltration
- The city recouped funds normally put toward road maintenance due to pervious pavement's lower life-cycle cost
- By reducing stormwater runoff on city streets, the Shoreview reduced snow and ice buildup on roads and the need for salt application
Shoreview has since used PaveDrain P-ACB pavements in six separate street reconstruction projects, five of which were on neighborhood streets.
Who Should Consider?
Towns or cities whose polluted stormwater runoff and proximity to waterways threatens compliance with federal regulations.