P.E. Rooftop gardens and other green roofing systems have emerged as methods for managing drainage and improving stormwater runoff quality.
Gardens require at least a foot of soil for landscaping and drainage systems.
Green roofs add up to 150 pounds per square foot of extra load to a structure, which must be accounted for during design. Buildings that incorporate green roofing elements may be eligible for grant funding under Section 319 of the Clean Water Act Section 319 of the Clean Water Act , which addresses nonpoint source pollution to lakes, rivers, and streams. Matching funds from local government agencies may also be available.