Severn River WQ Data Tracks Dead Zones, Great Clarity

Published: January 15, 2021

On top of all the trials we’ve experienced on land during 2020, the Severn River suffered through its own health crisis.

It was a year that saw extensive algae blooms and persistent dead zones that plagued the river through spring and summer and even into the late October.

And now, all of the water quality (WQ) monitoring data collected this year by the Severn River Association’s dedicated team of volunteers is available for review via the Chesapeake Data Explorer.

The Chesapeake Data Explorer is a tool designed through the Chesapeake Monitoring Cooperative that displays data from networks and organizations across the Bay watershed. Data is accessible to the public and can be used to inform and educate about the health of the Bay.

Click here to visit the Chesapeake Data Explorer system to study all the WQ data collected at each of our 44 monitoring stations throughout the Severn River.

SRA also wishes to thank our Field Investigator, Emi McGeady, for her work to complete the massive data upload that tracks conditions on a weekly basis at 44 monitoring stations throughout the entire river system.

SRA’s water quality monitoring program is designated with Tier II Status through the Chesapeake Monitoring Cooperative. This means that by following a set of scientifically sound protocols, our data meets water quality assurance standards and can be trusted by various regulatory, academic and scientific entities.

Some highlights from our special update, the Winter 2020 Water Quality Report include:

  • Dead zones persisted throughout then entire summer and into fall, not only in the main stem of the river, but especially in all off the creeks, from Weems Creek to the top of the river at Indian Landing Station near Ben Oaks and Pointfield Landing,
  • The worst water quality all season was consistently record at Indian Landing Station, adversely affected by the flood of nutrient-laden sediment flooding out of Severn Run and Bear Branch,
  • Oysters did well this year – no dead zones recorded at our oyster restoration reefs between the Rt. 50 and USNA Bridges, and
  • Oxygen and salinity levels at our Eaglenest Point monitoring station in Severna Park is on par with conditions below the Rt. 50 bridge, raising the prospect of a future site for oyster restoration.

Click here to read the entire Winter 2020 Water Quality Report. Highlights in the report include:

SRA’s water quality monitoring program is supported by a generous grant from Delaplaine Foundation.

SRA now has two years of water quality monitoring data shared on the Chesapeake Data Explorer.

When visiting the Chesapeake Data Explorer, you’ll have to zoom in on the Severn River to observe sampling events throughout the watershed. These are represented by the green dots in the map above. Users can download charts or raw data easily for all of SRA’s 44 monitoring stations.

Persistent Dead Zone In Brewer Creek

For example, when you visit Chesapeake Data Explorer and click on our monitoring station, Brewers Creek #2, one can investigate values for air temperature, dissolved oxygen, salinity, water clarity, water temperature, pH, and total depth through the 2019 and 2020 monitoring seasons by utilizing the drop-down menu.

Looking through the data at Brewers Creek #2 we observe a persistent dead zone in 2019 and 2020 when 75% of dissolved oxygen readings on the bottom of the creek were under the dead zone level of 2.0 mg/L.

Mid-River WQ Crew: Keith Madsen, Eric Madsen, and Rusty Rowles

This data is made accessible to us through the help of Keith Madsen, Eric Madsen, and Rusty Rowles, who surveyed 11 stations along the middle river weekly in 2020! See pic at left. Thanks guys!

WQ Crew Steve Small & Tom Guay measure record-breaking clarity: 3.16 meters.

Homogeneous Hypothesis

According to the Homogeneous Hypothesis, we expected to see high clarity when water temperature dropped below 16ºC.

And, our November tours offer proof of the hypothesis. Visibility in the river and creeks was just amazing in the early November.

Further utilizing the Chesapeake Data Explorer, we can see a jump in clarity in Saltworks Creek along with a drop in water temperature on November 5, 2020.

When water temperature dropped to 14.5 ºC, clarity reached a record 3.16 meters, or over 10 ft!!!  See picture at right of Capt. Steve Small and SRA Executive Director Tom Guay celebrating this amazing clarity.

Water temperature at Saltworks Creek #2 was the chilliest yet of the season –  14.5 ºC, on 11/5/2020.

Thanks to our many dedicated volunteers we are able to collect this data and share it with the scientific community.

Even in the trying year that 2020 has proven to be, we are still tracking the Bay’s health and understanding our great Severn River!