Stormwater Management & Green Infrastructure
Stormwater management is an extremely important topic in the City of Royal Oak. The city has implemented several methods to control the amount of stormwater entering the city’s sewer system to prevent basement back-ups caused by overloading of the sewers. The city has installed restricted catch basin covers to temporarily pond water on roadways, enacted a stormwater detention ordinance to limit the stormwater runoff from larger developments, and has recently started implementing green infrastructure projects throughout the city.
Restricted Catch Basin Covers
A 1990 study concluded that many sewers in the city could not handle 10-year storm flows. The city installed several relief sewers as well as restricted catch basin covers to slow the rate of flow into the sewers. Although these restricted covers cause temporary surface ponding on the roadway, they keep the sewers from overflowing and potentially backing up into residents' basements.
Storm Water Detention Ordinance §644
The city enacted a stormwater detention ordinance in 1991, which limits the stormwater runoff from commercial and multi-family properties. An estimated 2.1 million cubic feet of storage is currently in place, roughly 23% of total possible. Recently, the city added a variance to allow green infrastructure at the city engineer's discretion.
Stormwater Task Force
The Stormwater Task Force was created in 2016. The task force recommended the promotion of green infrastructure, revising the detention ordinance to allow GI implementation and to develop a stormwater utility.
Green Infrastructure is a broad term that describes several types of stormwater management practices including rain gardens, bioswales, permeable pavement, green roofs and rainwater harvesting. It is a method of storing stormwater using the natural environment rather than “grey infrastructure” such as sewer pipes and basins. Green infrastructure can help manage both the quantity and quality of stormwater.
Green Infrastructure Report
In 2018 the city had a green infrastructure study prepared, which evaluated ways to implement green infrastructure including several pilot projects, funding opportunities and a matrix of suitable plantings for rain gardens.
One way to mitigate stormwater from the city's sewer system is through rain gardens. Native perennials and shrubs are planted in a depressed area of land and are designed to soak in and store stormwater runoff from roofs, driveways, roadways, lawns, etc. The city has installed several rain gardens throughout the city at the following locations:
- E. Fourth Street parking lot, across from Grant Park
- E. Fourth Street, in the median between S. Blair Ave and S. Connecticut Ave
- Eagle Plaza Park biocells
- Vinsetta Boulevard, west of N. Main Street
- Worden Park (in front of Total Soccer)
- S. Main Street biocells
- Yorba Linda Boulevard, in the cul-de-sac island west of Fairmont Rd