Our Bay: ‘Flush fee’ at work in Anne Arundel
By PAMELA WOOD, Staff Writer, The Capital
Anne Arundel County is making your poop more friendly to the Chesapeake Bay.
With financial help from the state’s “flush fee,” the county’s Department of Public Works is modernizing six of its seven sewage plants so they send fewer harmful nutrients into rivers and the bay.
The largest and most complex of sewage plant upgrades, the Cox Creek plant in Pasadena, is the biggest single project the Department of Public Works has ever undertaken.
That project stretches across several years and will ultimately cost $163 million — more expensive than building a new high school.
Combined, upgrading all seven county-owned plants will cost $240 million.
The work is not exactly easy.
The plants have to be changed and expanded without being shut down. Just as much waste is being flushed into the sewage system on a daily basis, even as parts of the plants have to taken out of service to make the improvements.
“It’s like open-heart surgery,” said Chris Phipps, deputy director of the Department of Public Works.
Pollution diet
The work is aimed at helping the bay.
Maryland and the states that surround the Chesapeake are on the hook to comply with a federally-mandated “pollution diet.”
The states have to reduce the pollution from nitrogen and phosphorus that ultimately causes oxygen-deprived “dead zones” each summer.
The cleanup plans from both the state and the county rely heavily on upgrading sewage plants to meet the pollution diet requirements — both for the ultimate pollution diet deadline of 2025 and an interim deadline of 2017.
That’s because sewage plant technology is proven and there’s a steady stream of money to pay for it from the recently-increased “flush fee.”
The flush fee — officially called the Bay Restoration Fund — was established under former Gov. Robert L. Ehrlich Jr. in 2003 to pay for sewage plant projects. Part of the money also goes to upgrading septic systems and wintertime cover crops on farms.
State lawmakers raised the fee earlier this year from $30 per year to $60 per year. Most Anne Arundel residents pay the fee through their quarterly water and sewer bills.
“The money is being invested in great improvements,” Phipps said.
Plant upgrades
The county’s plants already are at “biologic nutrient removal” status, which means the water leaving the plants has no more than 8 mg of nitrogen per liter, compared to 35 mg of nitrogen per liter in untreated sewage.
Once the construction projects are complete, the plants will be at “enhanced nutrient removal” status, which is no more than 3 mg of nitrogen per liter.
The sewage plants were built at different times with different technologies, so the upgrade projects vary from one to the next.
At the Annapolis treatment plant off of Edgewood Road, the improvements include circulating sewage through the main treatment area more times, adding clarifiers to remove more tiny particles, adding denitrification filters and switching from disinfecting the treated water with chlorine to sterilizing it with UV lights.
It takes a few hours for sewage to travel from a home or business to a treatment plant. Then it takes another 24 to 30 hours to work its way through the plant’s treatment processes.
The contract to upgrade the Annapolis plant was awarded to MEB, a firm in Virginia. So far, work is on or slightly ahead of schedule.
Five of the county’s plants — Annapolis, Broadneck, Broadwater in south county, Maryland City and Patuxent near Crofton — will be complete in 2013 and 2014. Cox Creek will take until 2017.
The seventh county-owned plant in Mayo is taking longer to upgrade because its discharge pipe goes directly into a shellfish harvesting area, which complicates the construction design.
The county and state are weighing three options for Mayo: extending the discharge pipe further into the bay, pumping treated waste from Mayo to Annapolis to be discharged or pumping untreated waste from Mayo to the Annapolis plant.
A decision on Mayo will be made in 2013, following public meetings, Phipps said.
Reducing nitrogen
The seven county-owned plants currently discharge a total of nearly 450,000 pounds of nitrogen per year.
With the upgrades, and even accounting for increased sewage flow due to new developments, the pollution projection is 404,000 pounds of nitrogen per year in 2025, the target date for the federal pollution diet.
The county plants will actually be permitted to send more nitrogen into the bay, but aren’t expected to approach that cap until well beyond 2025. If the improvements weren’t made, Anne Arundel’s nitrogen pollution from sewage would inch up to 1 million pounds by 2025.
There are two other large sewage plants in Anne Arundel also in line for upgrades through the flush fee program — the privately-owned Piney Orchard plant in Odenton and the state’s Dorsey Run plant in west county.
Attacking pollution
On their own, Anne Arundel’s seven county-owned sewage plants are a small factor in Chesapeake Bay pollution, accounting for less than 1 percent of total nitrogen pollution that comes from the six-state watershed — about 450,000 pounds annually.
All pollution sources in the entire Chesapeake Bay watershed sent nearly 269 million pounds of nitrogen into the water in 2009.
The ultimate goal is to get that down to 201 million pounds by 2025 in order to get the bay off of the nation’s “impaired waters” list.
Statewide, the flush fee program will upgrade Maryland’s 67 largest sewage plants. Combined, the state’s upgrades will reduce pollution by 3.7 million ponds of nitrogen, according to the Maryland Department of the Environment.
So far, 26 plants are complete and 22 are under construction. Another 19 are in planning or design stages, according to MDE.
Other key source of pollution to the Chesapeake Bay include septic systems, urban and suburban stormwater runoff, farm runoff and air emissions.