Green infrastructure practices provide multiple environmental, economic and social benefits, including less polluted stormwater and increased property values. Examples of case studies demonstrating green infrastructure's economic benefits include:
- The Milwaukee Metropolitan Sewerage District (MMSD) purchases undeveloped properties in areas expected to have major growth in the next 20 years and natural areas along streams, shorelines and wetlands. The purchased acreage is estimated to hold over 1.3 billion gallons of stormwater at a cost of $0.017 per gallon. One of MMSD’s flood management facilities holds 315 million gallons at a cost of $0.31 per gallon.
- In Philadelphia, PA, officials learned that managing runoff through green infrastructure from 50% of the city’s impervious services would provide a net benefit of $2.8 billion, a net benefit 2,333% higher than managing it with a 30-foot tunnel, the traditional grey infrastructure option, which would provide a net benefit of $122 million.