October 31, 2018
WICOMICO RIVER CLEANS UP WITH NETTECH™ GROSS POLLUTANT TRAPS
Salisbury, MD
DESIGN & CONSTRUCTION TEAM
Client: City of Salisbury, MD
Project Coordinator:
Bill Sterling
Dept. of Public Works.
Utility Contractor:
Drainage Protection Systems
(DPS), a Division of Oldcastle
OLDCASTLE STORMWATER PRODUCTS INSTALLED
24” & 36” Nettech Devices, plus 30 Flogard Plus Catch Basin Insert Filters
The City of Salisbury, located in southeastern Maryland, is the county seat of Wicomico County and is also the largest city in Maryland’s Eastern Shore region. It is the commercial hub of the Delmarva Peninsula and is sometimes called “the Crossroads of Delmarva”. One of the focal points of the downtown area is a riverwalk along the Wicomico River which the city maintains.
When the City of Salisbury decided to make an effort to clean-up the trash and debris flowing into the Wicomico River from the adjacent contributing watershed, they chose Oldcastle Infrastructure’s NetTech™ gross pollutant traps (GPT) and FloGard Plus catch basin insert filters using a community development block grant. In February 2011, Drainage Protection Systems (DPS), a division of Oldcastle, installed a 24” circular GPT, attaching it to an existing 24” stormwater outfall pipe beneath the Division Street Bridge which is adjacent to the city’s riverwalk. Then in September 2011, a 36” circular GPT was installed on a nearby outfall pipe. The NetTech device will capture trash and debris from the outfall and contain the contents until the city’s maintenance crews pickup and dispose of the debris.
Once emptied, the netting device is reattached and the process begins anew. The NetTech, an end-of-pipe treatment device, was selected by the city due to the conspicuous location of the outfalls. Not only is the location highly visible by local residents and adjacent property owners, thereby providing an immediate showcase of the captured debris, it also allows appropriate maintenance accessibility for debris collection and disposal.
One of the most significant, yet unrecognized types of water pollution is stormwater runoff. When it rains, stormwater collects everything in its path, including trash, debris and other pollutants. Eventually, the water reaches streams or rivers, either over land or via storm drains. But unlike sanitary sewers that divert water to treatment plants, storm drains ultimately empty directly into surrounding lakes and rivers without any type of treatment. All of the debris and pollutants that were picked up by the stormwater eventually end up in our nation’s waterways.
The Baltimore shipyard is the U.S. Coast Guard’s active maintenance and repair facility for the Atlantic Fleet. This historic facility has served as regional headquarters, shipyard and depot since 1899. Currently, the shipyard employs over 1,500 personnel to overhaul and recondition ships, from propellers to defensive systems.
INSTALLATION ISSUES
The timing of the tidal-influenced Wicomico River had to be accounted for during installation due to the outfall pipe being partially submerged during high tide. Additionally, the upstream storm sewer system maintained a constant runoff through the pipe network, which had to be temporarily dewatered during the installation sequence.
DPS accomplished this through the use of sandbags and a sump pump in the adjacent upstream manhole, thereby providing for a relatively dry installation environment. Furthermore, access for the installation had to be considered due to the river’s proximity to the outfall. The city provided a boat to assist with the installation along the riverwalk, which was needed in conjunction with DPS’s boom-lift vehicle. Traffic was controlled along the Division Street Bridge during installation by the city, while DPS provided power access through a mobile generator which was necessary for properly securing each NetTech device to the outfall pipe. Total installation time took about four hours per unit.
RESULTS
The two NetTech units had an immediate impact by drastically reducing the amount of trash and debris deposited into the Wicomico River, thereby providing an enhancement to the city’s river beautification project. These installations were the first two completed portions of the city’s overall stormwater master plan. In May 2012, the city contracted with DPS to install 30 FloGard Plus catch basin insert filters within the watershed as well.
Though these are the first NetTech devices to be utilized in the Maryland Eastern Shore region, neighboring communities outside of Salisbury, including Talbot County and the City of Easton, have recently installed several NetTech units as well.
It is of the utmost importance to keep trash and debris out of our nation’s waterways, keeping our water as clean as possible for current and future generations, and Oldcastle Infrastructure is helping city and county agencies accomplish this task, one step at a time.