Green Infrastructure

In Pinellas County, we’re surrounded by water. Protecting the quality of that water is a top priority. Clean beaches and bays are important resources for wildlife, residents and tourists—and our economy.

Our countywide Strategic Plan calls upon us to engage in the best environmental practices. Green infrastructure helps us do that.

What is Green Infrastructure?

Green infrastructure is a term to describe practices that create habitat and allow rainwater to filter through vegetation and soil rather than running into storm drains.

In undeveloped areas, plants and the ground filter rainwater. In developed areas built with traditional methods, impervious cover like pavement and buildings prevent rainwater from soaking into the ground. Green infrastructure helps to filter rainwater more naturally. This minimizes the negative effects of development on the environment, and it reduces the long-term costs of treatment and maintenance.

Open the Green Infrastructure StoryMap in its own tab.

Green Infrastructure

  • Modern methods of stabilizing shorelines and managing rainwater
  • Focused on creating an urban landscape that allows water to penetrate into the ground and filter naturally (green roofs, bioswales, pervious pavement and living shorelines)
  • Protects air and water quality, provides habitat for wildlife and creates better flood protection

Gray Infrastructure

  • Older methods of stabilizing shorelines and managing rainwater
  • Primarily focused on collecting rainwater and directing it away from developed areas (curbs, gutters, pipes and storm drains)
  • Lacks habitat and dumps polluted water into lakes, bays and the Gulf of Mexico

How Impervious Cover Affects the Water Cycle

natural ground cover allows 40% evaporation, 10-20% impervious surface allows 38% evaporation, 35-50% impervious surface allows 35% evaporation, 75-100% impervious surface allows 30% evaporation
As impervious surfaces increase, water evaporation decreases.

Economic, Environmental and Social Benefits

Improved Water Quality

Stormwater filters through plants and soil at or near its source, reducing pollutants.

Reduced Flooding and Erosion

Runoff is greatly reduced because more water is absorbed where it falls, which in turn reduces flash flooding and erosion issues.

Habitat restoration

Florida-Friendly Landscaping™ plants provide food and a place to live for wildlife in an increasingly urban environment where non-native turf grass dominates the landscape.

Increased Groundwater Recharge

Rainwater filters through soil at its source, replenishing groundwater.

Cooler Temperatures

Less asphalt and concrete reduces the urban heat-island effect.

Less Climate Impact

Plants absorb carbon dioxide, a greenhouse gas.

Enhanced Community Aesthetics

Landscapes with green infrastructure can result in higher property values and faster property sales.

Reduced Energy Use

Tree shading and green roofs lead to less air conditioning use. Planted areas require less lawn mowing. Less gray infrastructure reduces the effort we spend on making and transporting materials like concrete.

Decreased Air Pollution

Trees and plants clean the air. Reduced energy use leads to lower power plant emissions.

Educational Opportunities

Green infrastructure sites can include informational signs and be used as outdoor classrooms, which educate the public about important environmental issues.

Expanded Community Value

More green space can lead to greater recreational opportunities.

Benefitting the Community

Keeps Beaches Open

In Venice, Florida, a dune treatment system that includes bioswales is removing 91 to 100 percent of nitrogen, phosphorus, sediment and bacteria pollution from stormwater before it discharges into the Gulf of Mexico. Health warnings at Venice Beach have been drastically reduced since the installation in 2015.

Saves Money

Green infrastructure reduces the amount of expensive gray infrastructure required, such as curbs, gutters and pipes. It also reduces or eliminates the need for large stormwater ponds and minimizes the pipes required to move stormwater.

Prevents Mosquitos

Green infrastructure used to manage stormwater is designed to return to dry conditions within 24 to 72 hours, which prevents mosquito breeding.

Reduces Maintenance

Plants selected will be resistant to both drought and temporarily submerged conditions; will not require watering once established; and will not require the use of fertilizer or other chemicals. Weeding and other incidental maintenance can be done by volunteers, homeowners associations or county staff, depending on the situation and level of interest.

Types of Green Infrastructure

A collage that depicts, from left to right: pervious pavement at Largo Mall, MacDill Air Force Base living shoreline and a bioswale in Auburndale, Florida. Overlaid with the text, Types of Green Infrastructure.
From left to right: Largo Mall pervious pavement; living shoreline at MacDill Air Force Base; and a bioswale in Auburndale, Florida.

Bioswale

A bioswale is a ditch or swale that has been modified and planted with Florida-Friendly Landscaping™ vegetation to increase pollutant removal and water infiltration.

Vegetated Filter Strip

Vegetated areas are designed to capture and filter stormwater while also absorbing carbon dioxide.

Rain Garden/Bioretention Cell

Rain gardens—also referred to as bioretention cells—are shallow depressions planted with Florida-Friendly Landscaping™ plants. They are designed to receive and filter stormwater runoff.

Trees to Intercept Rainfall

Leaves in the tree canopy capture water, reducing runoff.

Tree Filter Box

Reservoirs containing gravel, soil and vegetation (such as trees) are designed to collect and filter stormwater.

Pervious Pavement

Pervious pavement can be constructed from pavers or other porous surfaces that allow stormwater to filter through the pavement and into the ground underneath.

Green Roofs

Building roofs that are planted with vegetation capture rainwater and reduce runoff from the roof. They also reduce energy use and absorb carbon dioxide.

Stormwater Harvesting

Cisterns can be used to capture and store rainwater for later outdoor use, such as to watering non-edible plants.

Living Shorelines

Natural materials such as rocks, plants and oysters are used to prevent bank and shoreline erosion. Living shorelines provide habitat and improve water quality.

Going Green

Pinellas County Public Works is encouraging the use of green infrastructure. Public Works staff can work with developers and homeowners to explore new opportunities for green infrastructure in the county.

For more information, call 727-464-8900.