Large Apartment Building
Consider an intensive green roof system or a modest rooftop container garden. Take care of the city's curbside rain gardens on your block.
Featured Garden: A Manhattan High Rise With Two Green Roofs
Learn How to Do It
The most comprehensive approach would be to install a green roof. Granted, retrofitting a building with a green roof will require a committed co-op board or building owner and a significant investment. But besides mitigating storm-water runoff, there are other benefits: increased energy efficiency and usable outdoor space. BBG's handbook Green Roofs and Rooftop Gardens provides an overview of extensive and intensive green roof systems.
- If you can’t commit to a full green roof system, consider a more modest rooftop container garden, or at ground level, a courtyard or patio container garden. Include among your planted pots one or more open-top, watertight vessels (sans drainage holes) to harvest even more rain. Cover them with a screen to prevent mosquito infestation, and use the rain you collect to water your plantings.
- If you have a courtyard or front yard, you can also build an in-ground rain garden. Just avoid siting it directly adjacent to your building to avoid foundation leaks.
- Most large apartment buildings have internal drains that lead directly to the storm sewer, so you likely won’t be able to connect a rain barrel to it. But you may be able to connect one to a shed or awning.
- One simple strategy: Omit the curb around the plots between your building and the sidewalk. This will allow more runoff to flow into your garden instead of the drain.
- Become a bioswale steward. Bioswales are specially engineered sidewalk plots that look like tree beds—which many of them also are. Bioswales have features like curb cuts and underground drainage layers that allow them to hold extra rainwater when needed. The city began adding them in 2011 and will offer training for maintenance soon. In the meantime, simply keeping the curb cuts clear of litter will go along way toward keeping them effective.