Mayer/David Road Storm Drain Project

Why Here? Why Now?

The Mayer/David Neighborhood sits between the Capisic Brook and Fore River resulting in large amounts of fine silts and clays making up the base soils in the neighborhood. Since these soils drain slowly, intense rain events result in larger amounts of runoff as opposed to parts of the City with rocky loose soils. Fine soils also tend to expand and contract as the water concentration varies naturally, resulting in sidewalk and roadway degradation at a faster rate than we'd expect in better draining parts of town. A major part of this project will be installing underdrain to keep moisture from building up under the edges of the roadway and infiltrating only within systems designed to drain quickly without expanding.

The proximity of the neighborhood to the Capisic Brook also allows for stormwater discharge without having to route expensive storm drain far outside of the neighborhood or without the potential for creating flooding elsewhere that is not prepared to handle stormwater flows from outside of its watershed area.

Planning for this project began in 2020 after a Sewer overflow occurred. The City has also received complaints of icing in the roadway that creates dangerous driving conditions in the winter time. The sewer lines in this neighborhood are in largely good condition, but are undersized to handle the amount of stormwater that can enter the system during large storm events. As the climate changes, the expectation for Portland is that we will receive less frequent but more intense storms. Separating the combined sewer system will proactively remove stormwater from the sanitary sewer before the larger storms of the future have a chance to cause sewer back-up or overflow within the neighborhood or into the Casco Bay.