Earth, Part 2: Green vs. grey infrastructure

No simple solution

Drains overflow with heavy rain or snow.
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Drains overflow with heavy rain or snow.

Green infrastructure has gained popularity recently as a means for local communities to manage water in a way that protects and restores natural water cycles. It’s popular with many because it’s visible and improves urban environments. It includes using natural means of water filtration to retain and clean water, such as planting more trees and creating more and better green spaces, as opposed to building new water treatment facilities.

The problem in Bayonne is that there isn’t much available space for green infrastructure to capture enough water to make a big difference. A less discussed solution is the invisible, underground, “grey” infrastructure that may help meet Bayonne’s environmental objectives. Grey infrastructure includes pipes, pumps, ditches, retention ponds, and holding tanks.

In Bayonne, the major focus of environmental protection is its surrounding waterways. When it rains or snows, the city’s old sewage system dumps untreated sewage and water runoff into Newark Bay, the Kill Van Kull, and the Hudson River through 31 outflows. Included in that untreated sewage is human feces, oil from cars, chemicals from lawns, plastics, and many other chemicals harmful to the environment.

Original sin

Bayonne is a natural estuary, and in hindsight, should probably never have been developed into a permanent settlement. But here we are, with impervious roads that don’t allow water to filter through the soil, cars with combustion engines that pump carbon dioxide into the air and oil into the water, and buildings that replace the wetlands that would otherwise host vibrant ecosystems.

“Green infrastructure makes up only five percent of the solution,” said Tim Boyle, executive director of the Bayonne Municipal Utilities Authority. “And it’s really costly.”

No exact figures are available as to how much water can be captured by green infrastructure versus grey infrastructure in Bayonne. City officials know there is more space underground than there is above. And even above ground, most of the land where green infrastructure could be installed is owned privately. Right now, there is no way to force property owners to use green infrastructure.

“It’s hard to install green infrastructure,” Boyle said. “Rain gardens can turn into litter collectors, and tree pits can only be done in certain areas.” A tree pit is a large water tank installed underneath a tree that captures water.

Tank you

Another idea for a grey infrastructure project is a 2.5 million-gallon tank on Oak Street that used to be a treatment plant. Water is periodically removed from the tank and transported to a water treatment plant.

“We have to figure out how to put that tank into service,” Boyle said. “In other areas we are going to have to find ways to add cisterns, retention ponds, things of that nature.”

Permeable surfaces, such as permeable roads and parking lots, can be expensive to install. Pipes run underneath, which makes them hard to dig up.

Public buy-in 

Despite Boyle’s criticism of green infrastructure, it remains one of the best ways for residents to perceive how our developed environment has negative consequences on the natural environment. Rain gardens and trees are pleasant to look at. Planting more of them is nearly universally supported.

Solutions to the problem may involve throwing everything at the wall and seeing what sticks. The best solution may be whatever the most people will support.

For updates on this and other stories visit hudsonreporter.com and follow us on Twitter @hudson_reporter. Rory Pasquariello can be reached at roryp@hudsonreporter.com.