Western Regional Park Wastewater Treatment Plant
Location Howard County, MD
Client Howard County Bureau of Utilities
Size 5,250 GPD
Costs $3,350,000
Date of Completion 2020
Services #Architecture #Construction Services #Consulting #Structural Engineering #Water / Wastewater Engineering
GMB was hired by Howard County Bureau of Utilities in June 2014 to provide a Preliminary Engineer Report (PER) for the facility.
PER recommended:
- Consolidation of the Library, Community Center, Fire Station and Park Facilities with low pressure sewer for treatment
- New State of the Art Membrane Biological Reactor (MBR) treatment system to treat to 10 mg/L TN or better (i.e. below drinking water limitations in groundwater)
- Modification of the permit to consolidate disposal into one (1) drain field with 7300 gpd capacity.
- Provisions for potential reuse application in the future.
Project Summary
- Facility designed to treat 3650 gpd ADF at 10 mg/L resulting in over 75% reduction in nutrient load to the groundwater.
- Four (4) pumping stations with converted septic tanks for emergency overflow.
- 3500 LF of directional drilled low-pressure sewer
- Flow Equalization Tank with mechanical mixer
- Influent Screening Manhole
- State-of-the-art mini-MBR supplied by ITP
- Permeate discharge to drainfield
- Chemical Storage and Feed Systems
- Sludge Storage tank
- Vent Odor Control at Sludge Tank and Pumping Stations
- Effluent Storage Tanks with chlorination loop for future reuse applications.
- Lab/Office/Restroom for operations
- Building Exterior modeled to be similar to other park buildings.
- Site History:
- Glenwood Library ~ 1999
- Western Regional Park ~ 2002
- Gary J. Arthur Community Center ~ 2004
- Glenwood Fire Station ~ 2011
- Library, Community Center and Park Facilities served by five (5) separate septic drain fields for wastewater treatment and disposal under rules at the time limiting capacity per drainfield.
- Prior to building the Fire Station, MDE changed groundwater disposal permit requirements for large systems to include parcels with a total drain field capacity over 5,000 gpd.
- Changes by MDE in drain field permitting imposed a ground water discharge permit for the parcel requiring nitrogen treatment capped at 246.6 pounds per year (4,050 gpd ADF @ 20 mg/L TN)
- With the regulatory changes, installation of a drain field for the Fire Station was not feasible. The Fire Station construction included a storage tank requiring a costly pump and haul operation until treatment could be provided.
- The initial Groundwater Discharge Permit was received on July 7, 2014 with an effective date of September 1, 2014 to consolidate the wastewater to meet the new treatment limits.
- Design of the new low-pressure sewers and treatment facilities began in March 2015.
- Groundwater disposal permit modifications were received in May 2017 to accommodate the design. Rerating of the existing drainfield was received in February 2019.
- Project originally bid in 2017. Bids received exceeded the budgeted funding.
- Project was redesigned and additional funding obtained to re-bid in September 2018. Redesign focused on one (1) MBR supplier for the project. ITP’s mini-MBR was selected for this project.
- ACE was awarded the contract for $3,350,000 with NTP issued June 26, 2019.
- Project achieved Substantial Completion on June 25, 2020 after successfully demonstrating treatment to meet or exceed the permit requirements.
- Project completed within the project schedule and construction budget even considering the challenges created by the COVID pandemic occurring 3 months prior to the scheduled end date.
