Irene's Impact on Severna Park Area Waterways was Minimal

A little more than one week after Tropical Storm Irene passed by our area, Patch took a look at how local waterways were impacted by the storm's wind and rain.

We all know that some man-made things had it rough, like above-ground utility wiring. Some old trees also had a hard time weathering the storm.

But what about the plants and animals that live in the Chesapeake Bay and tributaries? What about water quality due to runoff and storm surge?

We talked to Bruce Michael, director of resource assessment at the Maryland Department of Natural Resources and Chris Trumbauer, the West/Rhode Riverkeeper, about how nature fared during and after the storm.

Michael said the main issue with most hurricanes is storm surge and a rush of nutrients and pollutants entering the water due to flooding.

“Flooding wasn’t that big an issue on the western shore, but on the Eastern Shore, the Choptank and Tuckahoe Rivers, they experienced a record high peak flow—more than we’ve seen in 60 years,” Michael said.

Trumbauer said water samples taken after the storm showed some changes in water quality. Salinity decreased due to heavy rainfall—and an influx of freshwater—and water clarity was worse because everything got stirred up.

He said that neither of these issues have serious implications.

In fact, Trumbauer said he didn’t believe Irene, in the short term, did much harm at all.

Michael said the “dead zone,” an area of the bay that scientists keep a careful watch on during summer, was nearly completely broken up.

“It was completely disbursed, except in one area where the Patuxent River comes in. The whole rest of the bay was destratified,” Michael said.

And that is a good thing. Scientists have watched the dead zone grow a little larger each year.

But the dead zone is usually broken up by mid-September anyway, because of cooler weather and a pattern of cold fronts that move over the bay.

Michael said fall storms are typically not as bad for the bay as spring storms.

“The grasses are coming up [in the spring], fish are spawning, so a storm in the spring is more critical,” he said. “In the fall, the grasses naturally die back.”

In addition, the storm may have helped to dissipate algae blooms.

This year was unusual, even outside a big weather event like Tropical Storm Irene, because of the rainy spring.

“We received the amount of flow from the Susquehanna over Conowingo Dam—what we usually see in a whole year had come over by mid-May,” Michael said.

Trumbauer said Irene also helped the bay because the winds from Irene pulled water out of the bay.

“Any storm surge that came up the bay was canceled by the winds blowing water out,” he said.

“In fact, it blew out most of the jellyfish,” Trumbauer said.

So it seems the bay and area waterways and tributaries fared better than some old trees and power lines during Irene.

“Obviously, this was a big rain event, and whenever you have that, it flushes lots of nutrients and runoff; sediments from farmers’ fields. Plus, any type of destruction like downed trees and shrubs has an impact,” Michael said.

“But will it bounce back? Absolutely," he said.