The Many Benefits of Green Infrastructure

Green infrastructure includes projects that mimic the natural environment to manage stormwater runoff, improve air quality, and cool temperatures throughout the city to mitigate the urban heat island effect.

New York utilizes a variety of green infrastructure to collect and control stormwater that could otherwise flood streets or overflow the City’s sewer system. A combined sewer system is used in approximately 60% of New York City. In the event of heavy rainfall, sewage treatment plants cannot handle the volume of water pouring in, causing rainwater and untreated sewage to pour directly into the City’s waterways. Since these overflows negatively impact water quality, green infrastructure is essential in mitigating this threat.

Common types of green infrastructure for stormwater collection include:

  • Rain Gardens: Typically found on sidewalks, rain gardens are small, planted areas with various types of vegetation. Usually plotted in depressions with deep layers of sandy soil and stone, water is able to infiltrate and collect inside the rain garden.
  • Stormwater Greenstreets: Although similar to rain gardens, stormwater greenstreets tend to be much larger and often include taller and wider vegetation, based on the needs of the roadway where it is placed.
  • Permeable Paving: To allow rainwater to directly flow between or onto porous materials, permeable paving is used instead of concrete or asphalt to absorb and collect excess water.

In addition to stormwater management, green infrastructure initiatives often provide other benefits, such as reducing air pollution and lowering temperatures during heat waves.

New York also experiences high levels of ozone pollution and smog formation, mostly from automobile emissions. These air pollutants are hazardous for human health, causing coughing fits, shortness of breath, and asthma attacks. During the summer, these health risks are amplified. Older and at-risk populations are more susceptible to dehydration and heat stroke. In big cities, the urban heat island effect makes cities hotter in comparison to green spaces or rural locations, as concrete, asphalt, and other manmade materials absorb more solar energy.

Green infrastructure used to mitigate issues related to air quality and temperature are:

  • Green roofs: Usually designed as a large spread of plants across a roof, green roofs are hugely beneficial. Green roofs lower temperatures and remove heat from the surrounding environment as the plants perform evapotranspiration and release water back into the air. These projects also collect stormwater, so many types of vegetation can grow on top of roofs using this method.
  • Trees, park, and green, open space: More green means lower temperatures and decreased air pollution. Trees and plants provide shade and perform evapotranspiration, cooling down surrounding areas. Vegetation can also provide permeable barriers, forcing polluted air to take a longer path between the emission source and people inhaling the air. This reduces pollution by mixing it with the surrounding air, diluting the concentration of pollutants. In the process of deposition, some pollutants even stick to leaves instead of persisting in the ambient air. Green spaces also promote less driving by encouraging people to walk or bike through these areas.

Green spaces are advantageous for the natural environment as well as human health. The recent Environmental Bond Act, passed as part of the state budget and appearing on ballots in November, prioritizes these important green infrastructure projects and allocates $3 billion to reduce flood risk, improve water quality, restore natural habitats, and minimize pollution.

Outlined within the Bond Act are plans to protect communities from flooding and increase their water quality, meaning that it could fund rain gardens, stormwater greenstreets, and bioswales to collect and manage stormwater more efficiently. Green roofs and permeable pavement could be employed to improve water quality by reducing the volume of untreated sewage flowing into New York’s waterways and allow it to go to the treatment plants. Restoration is another large component of the Bond Act, which provides other environmentally-based solutions to flooding, reducing temperatures across the city, preventing natural pollution, and protecting ecosystems.

NYLCV strongly supports New York’s green infrastructure solutions, and the Environmental Bond Act can be an effective way to increase the number of green infrastructure projects across the state.