When you flush a toilet on Center where does it go?
Well the answer is the Hampton Roads Sanitation District (HRSD). LaRC’s sanitary piping, which primarily carries discharges from sinks and toilets, discharge to HRSD for treatment. HRSD, a political subdivision of the Commonwealth of Virginia, was created by public referendum in 1940 to eliminate sewage pollution in the tidal waters of the Chesapeake Bay. HRSD owes its creation to oysters, a robust seafood industry in the early 1900s. The Virginia Department of Health condemned a large oyster producing area in 1925, bringing the question of sewage pollution to light.
HRSD facts include:
- Year Created: 1940
- Type of Agency: Political subdivision of the Commonwealth of Virginia
- Service Area: 17 counties and cities
- Population Served: 1.6 million
- Governing Body: Governor-appointed commission
- Collection System: More than 500 miles of pipes, 6-66 inches in diameter
- Pump Stations: 104
- Treatment Plants: 9 major plants in Hampton Roads and 4 smaller plants on the Middle Peninsula
- Combined Capacity: 249 million gallons per day
You can visit HRSD’s webpage here: https://www.hrsd.com/
LaRC and HRSD – A Permitted Partnership
LaRC is classified by HRSD as a non-significant industrial user. We are a permitted entity and must adhere to HRSD’s industrial wastewater regulations as well as the individual permit itself.
What does this mean to you? If your facility is planning on discharging any wastewater to the sanitary system you need to get an Environmental review of the process. LaRC’s Environmental Management Office will work with HRSD on getting authorization to discharge, amend our permit, or we may require a different discharge strategy altogether. If your facility is changing processes, draining equipment (closed loop chiller systems, cooling towers, etc.), changing approved products, drainage piping, etc. please remember to coordinate with Environmental staff through the LF 461 process or call Ande Remington at 864-8332.
Inflow and Infiltration (I&I)
Inflow is stormwater that enters into sanitary sewer systems at points of direct connection to the system. Potential sources of inflow include footing/foundation drains, roof drains or leaders, downspouts, drains from window wells, and groundwater/basement sump pumps. These sources are typically improperly or illegally connected to sanitary sewer systems, via either direct connections or discharge into sinks or tubs that are directly connected to the sewer system. These types of discharges should be plumbed to the storm system or discharged directly to the ground to help recharge groundwater supplies. Also, NASA has to pay HRSD for treatment of clean stormwater.
Infiltration is groundwater that enters sanitary system through cracks and/or leaks in the sanitary sewer pipes. Cracks or leaks in sanitary sewer pipes or manholes may be caused by age related deterioration, loose joints, poor design, installation or maintenance errors, damage or root infiltration. Groundwater can enter these cracks or leaks wherever sanitary sewer systems lie beneath water tables or the soil above the sewer systems becomes saturated.
Cracked sewer pipe.
NASA and HRSD have been working hard to eliminate I&I issues. In fact, NASA is under an Administrative Order from HRSD to correct the problems on Center. To address this, NASA awarded a contract in July 2013 to upgrade the sanitary sewer system. In order to build a strong scope of work and award this contract, NASA had to perform a comprehensive analysis of potential I&I issues and document the health of the sanitary sewer system. The analysis included:
- Basement, utility tunnel, and parking lot sumps/pits were evaluated based on conversations with LaRC personnel, dye testing, and a review of previous assessments;
- A total of 175 locations were observed to include manhole lids, manhole structure, and surrounding topography;
- Vitrified clay and terracotta lines were smoke tested to check for collapsed/broken pipes;
- Dye testing was used to verify potential cross connections between storm drains and the sanitary sewer;
- Cooling towers were investigated to check for excess water discharge into the sanitary sewer;
- Lift stations and the overflow tank (southwest of Building 1256C) were observed to assess general condition;
- Personnel at LaRC were interviewed to identify potential chronic sanitary sewer problems;
- An engineering review was performed of a previous sanitary study;
- Abandoned lines resulting from demolished buildings were identified; and
- Previous tactical/design tasks that involve sanitary sewer upgrades were reviewed and included.
From this comprehensive analysis, a detailed scope of work was developed. The following is a brief summary of repairs and projects that are currently underway by the contractor:
- Fifty-one (51) low lying manholes will receive new internal seals and inflow dishes.
- Ninety (90) manholes will be thoroughly cleaned and sealed with an epoxy liner.
- Four (4) manholes will receive major repairs including excavation to barrel depth and the riser removed, a new gasket at joint will be placed and riser realigned (major repair).
- Seven (7) manholes will be totally replaced.
- Thirty-two (32) cleanouts will be addressed (broken, missing, or wrong sized caps to be corrected)
- Forty-seven (47) cleanouts that were not found in the field will be identified and repaired as appropriate by the contractor.
- A significant amount of sanitary sewer system repairs and upgrades are underway. These include cutting and capping abandoned lines, repairing and resealing the sanitary overflow tank at the pumping station, removing and replacing 2,275 linear feet of terracotta and vitrified clay lines with PVC pipe, repairing the boiler blow down pit to keep rainwater out, and a host of other repairs.
Do you have any ideas on how to eliminate I&I on Center? If so, please contact Ande Remington 864-8332.
