SAN DIEGO — While some people pay a premium for parking, most cities have too much. It's estimated that the U.S. has eight parking spaces for every car.
More than an eyesore, policy experts say America’s problem of excess parking is also hazardous to the environment.
“You have automobile fluids, pet waste, trash that falls out of your car. All of that gets picked up when it starts to rain, and becomes stormwater runoff, and pollutes our ocean," said Lucero Sanchez, community policy coordinator for San Diego Coastkeeper.
Dedicated to protecting and restoring our waters, the nonprofit combines science, advocacy, education, and community engagement to address existing and emerging water-related issues.
Sanchez says an oversupply of asphalt disrupts nature’s plan for rainwater.
Parking lots and other hard surfaces, like sidewalks and roads, prevent rainfall from soaking naturally into the ground. Large amounts of surface water polluted by contaminants like oil and antifreeze can enter waterways through storm drains.
“The increased heavier, more erratic rainy seasons are increasing the amount of flooding and really putting much more strain on already crumbling infrastructure," said Sanchez. "Causing failures in our systems, which end up being emergency issues," said Sanchez.
The nonprofit is calling on city leaders to address failing infrastructure and to establish a dedicated funding source to meet ongoing stormwater maintenance and repair needs.
"The longer we wait, the more issues we're going to have," said Sanchez. "The more flooding and property damage people are going to feel."
In a report card evaluating water infrastructure, the American Society of Civil Engineers (ASCE) gave the U.S. a grade of D. In the 2021 report, many of the country’s legacy stormwater systems are struggling with the high cost of retrofits needed to address urban flooding and climate change.
The ASCE says green infrastructure provides benefits by reducing runoff, minimizing erosion, and contributing to water quality improvements. Examples include rain gardens, constructed wetlands, vegetative roadway bioswales and permeable pavements.
"Really at the core of it, instead of having gray infrastructure, it's green infrastructure," said Sanchez. "It's having those nature-based solutions that mimic, protect and restore our natural water cycle.”
Researchers from The Nature Conservancy (TNC) and 2NDNATURE are using satellite imagery to help fill gaps in understanding how green stormwater infrastructure influences hydrology. The data showed urban greenness had significant influences on downstream flow responses.
The Environmental Protection Agency (EPA) offers tools and resources on how communities can implement green infrastructure.
"It’s something that is absolutely going to affect everyone," said Sanchez. "And even if you just stop for a second and think how many times you’ve had to go around flooding or you haven't been able to go to the beach. It is absolutely something that, no matter what income level you have, it will affect you.”