(Credit: Biohabitat.)
Spa Creek Conservancy led a volunteer water monitoring effort that sparked a restoration project to improve water quality and natural wildlife habitats.
Located in Annapolis, Maryland, the headwaters of the Spa Creek watershed flow directly into the Chesapeake Bay. The creek is an ecologically unique area that connects a narrow freshwater, non-tidal area to a much larger tidal area.
For years the freshwater headwater area has been the site of suburban development, with residential and commercial properties sprouting up regularly. During heavy rain events, the water runs off paved surfaces and into a storm drain system, taking with it all of the surface pollutants and depositing it all directly into Spa Creek.
Over time the pollutants – which include fertilizers, loose soil, oil and gas residue and other sediments –caused the erosion of the headwaters and floodplains leading to Spa Creek. This drastically affected the native wildlife and caused the creek to be classified as a highly impaired urban watershed.
Spa Creek Conservancy, a volunteer organization dedicated to the stewardship of the Spa Creek watershed, formed in 2004 and has become a trusted advisor on environmental concerns to the local community.
Members of the conservancy completed training with the Anne Arundel County Watershed Stewards Academy that requires 10 class sessions and capstone project including a community assessment, outreach and education and the installation of a small restoration project.
“Spa Creek Conservancy is considered very leading edge,” said Joe Berg, a senior ecologist with Biohabitats, which developed and led the design-build project. “They’ve been doing this work for over a decade. The community trusts them.”
The group and its volunteers began monitoring the headwaters using YSI Pro2030 and YSI 85 handheld meters. The meters measure several water quality variables including dissolved oxygen, salinity, conductivity, barometric pressure and temperature. The group also used water sampling kits to test for chlorophyll A, nitrogen, and phosphorous.
The results showed what the community’s eyes could already see, oxygen levels were low and nutrient levels were high.
“You could see sediment coming out of the stormwater system during high storm events. The water was very muddy and Phragmites, an invasive grass, was growing and spreading in the sediment deposits in the streams,” Berg said.
According to Berg, the speed of the traveling water was the source of most of the natural habitat damage.
“The top 800 feet of Spa Creek was a region of failing gabion baskets which are unhealthy for the stream. They allowed the water coming out of the storm drain systems to pick up speed and move very quickly,” Berg explained. “When the water came off the gabion basket channel into the narrow tidal headwater area it caused a lot of harm. It peeled up the tree roots, down cut and widened the channel, and transported a good deal of sediment downstream.”
With the heavy sediment load came the Phragmites, which made it hard for native birds to wade into the water and catch fish. The speed of the water eroded and lowered the creek bed, disconnecting it from the floodplain and the lower tidal area. This prevented fish from the lower end of the creek from swimming upstream to release eggs. With the fast-moving water regularly destroying beaver dams, the local beavers also weren’t thriving. The excess sediment prevented native underwater grass from growing, which deprived fish and crabs of their habitats.
Local wildlife was in decline.
Spa Creek Conservancy set its sights on restoring the headwaters and took action. The organization applied for, and received, a grant from the Maryland Department of Natural Resources’ Chesapeake and Atlantic Coastal Bay Trust Fund. The grant made it possible to restore 5,000 linear feet of stream. Biohabitats was hired to develop a restoration design and used Meadville Land Service to do the construction.
The Biohabitats team, led by Berg, included a design engineer, wetland scientist, and soil scientists. The team was determined to provide a design that supported the local ecology in a way that was healthy for Spa Creek and its wildlife.
A major component of the restoration plan included raising the headwater stream bed. In order to do that, the team needed to be granted access to 17 residential properties and permission from the City of Annapolis. To accomplish this, Spa Creek Conservancy and Biohabitats conducted community relations meetings to explain the situation and the restoration plan.
They were able to get permission from the residents and the City.
“It’s a remarkable thing that we were successful with all of the residents. That’s a great credit to the Spa Creek Conservancy,” said Berg.
Residents didn’t just provide access to their properties. Some of the younger residents worked to remove Phragmites.
“After Meadville Land Services excavated the Phragmites and most of their roots, we hired a local church group (READY) that introduces inner city kids to the environmental industry and to green jobs,” Berg said. “Ten kids go out every week and walk through the marsh and pull any of the Phragmites they see.”
Removing the 800-foot stretch of gabion baskets and widening the headwater area was crucial to reducing the speed of the storm water. In place of the gabion baskets, a step-pool system was installed. Step-pool systems are a mix of sand and woodchip over existing ground. Cobbles and boulders are put over top in a descending curved path that mimics steps. The step section is followed by a small pool area that ranges in depth from 18 inches to four feet to catch some of the water and decrease the both the amount of water and the speed. Native plant life is also placed along the system to help filter sediment and create a habitat. The path alternates between a step section and pool section.
The second area of focus was the beaver marsh. The main stream that flowed through the marsh was five foot deep but only three foot wide. Anytime that there was a heavy rain, the velocity of the water would wash away any progress that the beavers made on their dams. The team employed a technique using willow wattles, which are like one foot diameter logs that are made out of all the fine stems of Willow.
“We installed willow stakes by hand so that no construction equipment needed to enter the marsh and cause further damage,” said Berg.
The team installed the willow wattles and 12 beaver dam analogs further upstream. Now when the water travels down onto the floodplain, out into the beaver marsh, it slows down and backs up. This will allow the beaver to continue their daily work.
Next, the team needed to connect the lower stream to the upper stream again.
“We raised the bottom of the stream downstream of Spa Road by about a foot. So now there’s six inches of water in the culverts under Spa Road,” said Berg. “So now fish can move from the bay up into the beaver marsh and upstream from there. So that’s really opening up a fish habitat where white and yellow perch can breed.”
With the three restoration techniques in place, scientists with Biohabitats will monitor the stream.
“We’ll go out next spring when it starts greening up to check for, and remove Phragmites” said Berg. “Then we’ll plant tidal shrubs and marsh plants.”
The monitoring will continue for the next five years to make sure that the new structures are properly installed and performing as intended. Biohabitats also installed data loggers in the stream that measure water pressure. In the future, the data will be available to Spa Creek Conservancy.
The data will also be used in presentations.
“We would like to show our peers, regulators, and other organizations like Spa Creek Conservancy why and how this works,” said Berg. “Then hopefully they will adopt and implement similar projects.”
Spa Creek Conservancy is happy with the results.
“The restoration of the headwaters has been an amazing project,” said Amy Clements, president of Spa Creek Conservancy. “It has generated lots of enthusiastic support from funders, the city, neighbors, communities, other watershed organizations and passersby.”
Clements led walk-throughs of the area before the restoration began and will be holding more this winter when the restoration is complete.
Top image: (Credit: Biohabitats.)
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