Question: Green roofs in Philly, so how about Cleveland?

Several tweets came across our “stormwater” feed over the last week discussing the City of Philadelphia’s $2 billion green-infrastructure stormwater control plan. …

The news prompted a great Facebook question, asking whether our Regional Stormwater Management program would offer a “subsidy for green roofs,” similar to the credits we propose for residential stormwater control measures. Our Watershed Programs department had an answer.

Green roofs indeed are options for credits under the Regional Stormwater Management Program, and may be part of a larger project in the future, but there are very limited circumstances where the District would pay for a green roof because there are generally lower-cost and better stormwater management options available.

Outside of highly urbanized environments, such as downtown Cleveland, green roofs actually are one of the least preferred stormwater control measures in areas such as Northeast Ohio where there is land often available for lower cost and more effective stormwater control measures such as bioretention areas, bioswales, and other landscape features. The energy-saving and heat-island control benefits of green roofs often outweigh their direct stormwater control benefits. However green roofs are one of a range of stormwater control measures property owners can explore for credits.

The District will provide direct funding for certain stormwater control measures as part of the green infrastructure program under Project Clean Lake, our combined sewer overflow control consent decree. These stormwater control measures however must meet specific stormwater quantity capture and infiltration standards which green roofs will most likely not be able to meet.

We remind readers that our proposed regional stormwater management program has not been enacted. It is in litigation, and we will keep customers informed as we move forward.