Magothy River Health Showed Mixed Results Again In 2021

The Magothy River Association (MRA) held its annual State of the Magothy in March, sharing that the Magothy’s health has declined.

The findings are based on MRA’s annual Magothy River Index, first presented in 2003, which assesses water quality in the tidal river. The index is based on three criteria established by the Chesapeake Bay Program for ecosystem health, and is expressed as percent attainment of a desirable goal and as a letter grade where 0% to 20% is an F, 21% to 40% is a D and 41% to 60% is a C. The criteria are percent attainment of water clarity based on Secchi disk depth of at least 1 meter; dissolved oxygen of at least 5 milligram per liter in the deepest water at each station and achievement of the Chesapeake Bay program goal of 579 acres of submerged aquatic vegetation (SAV).

SAV requires water clarity for growth and provides dissolved oxygen as well as key food and habitat for fish and crabs while reducing the impact of wave action on the shore. Most fish, shellfish and aquatic invertebrates require at least 5 milligrams per liter of dissolved oxygen in the water column for their growth and reproduction.

In addition to the SAV coverage, this year’s index is based on data collected by volunteers from eight open water mainstem sites, two upstream mainstem sites and 20 creek or cove sites sampled from piers. MRA did not include the most upstream site of Cattail Creek in the final index since members do not sample in the headwaters of any of the other creeks. This year’s index is 23.4, which is a D.

There was some good news: the river had a robust yellow perch span. But overall, MRA president Paul Spadaro sees room for improvement.

“The takeaway from this year's State [of the] Magothy is that we must do a better job of controlling the nutrients that wash into the river,” Spadaro wrote in a statement. “One way of doing this would be to plant more trees in the watershed, which will help absorb these nutrients.

“And we must renew our efforts to control development. Communities that fight back win back. Working together we can and we will restore the Magothy for the generations to enjoy.”