City of Phoenix Testing 'Cool Pavement' Program

PHOENIX — The City of Phoenix will roll out cool pavement treatments on streets in select neighborhoods as part of a pilot project. The city is considered a "heat island" and the cool pavement could help to offset rising temperatures.

The city's Street Transportation Department has partnered with the City of Phoenix Office of Sustainability and Arizona State University to operate the program and research the impacts of the new cool pavement. Eight neighborhoods were selected to receive the coating, and it has already been completed at Esteban Park in south Phoenix.

"We plan to engage university researchers to take measurements and collect data over several years," the city said of the program on its website. "They will evaluate the results and will hopefully help us understand if the cool pavement product helps mitigate the heat island effect and if those effects are sustainable over time."

The coating is made with asphalt, water, soap, mineral fillers, polymers and recycled materials, and is applied to existing pavement. It contains now harmful chemicals and is safe for pets and vehicles. Cool pavement is light gray in color and reflects back the sunlight instead of absorbing it like typical asphalt. Asphalt absorbs heat throughout the day and releases it at night, contributing to rising nighttime temperatures and creating what is called a "heat island."

Data from the U.S. Environmental Protection Agency reveals that the difference in nighttime temperatures in heat islands can be up to 22 degrees hotter than in areas outside of them, according to the city of Phoenix.

Local streets from each council district in the city were chosen for the pilot project. The city said the chosen streets were selected because the existing asphalt is in good condition and the treatments will improve road condition. The tentative schedule has work beginning mid-August on Roosevelt Street and Van Buren Street downtown. It is due to end in October with work on Vineyard Road and Southern Avenue.

Anyone who lives on the streets in question will receive advance notice.