Water quality modeling experts have announced a drop in estimated nutrient and sediment loads entering the Chesapeake Bay. Computer simulations show that pollution controls put in place between 2009 and 2015 have reduced the amount of nitrogen, phosphorus and sediment entering the Bay by eight, 20 and seven percent. During the 2014 to 2015 reporting period alone, these controls reduced nitrogen, phosphorus and sediment loads by three, three and four percent. Experts attribute this drop to significant reductions of nitrogen and phosphorus in the wastewater sector, reductions in the atmospheric deposition of nitrogen as a result of the Clean Air Act and the increased implementation of agricultural conservation practices. Improved reporting and enhanced crediting of these practices have also generated a more accurate picture of the pollution entering rivers and streams from this sector.
Excess nitrogen, phosphorus and sediment impair water quality: nutrients can fuel the growth of algae blooms that lead to low-oxygen “dead zones,” while sediment can block sunlight from reaching underwater grasses and suffocate shellfish. The pollution load estimates discussed here are one in a suite of tools used to track progress toward our clean water goals, which include the pollution-reducing commitments of the Chesapeake Bay Total Maximum Daily Load.
Nutrient reductions in the wastewater sector account for 41 percent of the estimated Bay-wide nitrogen reductions and 38 percent of the estimated Bay-wide phosphorus reductions that took place between 2014 and 2015. Indeed, many large municipal wastewater treatment plants are removing more nitrogen from effluent than it was previously thought technology would allow.
Our picture of agricultural best management practices has also changed: cover crops have seen improved reporting, conservation tillage has seen increased implementation and nutrient management plans have become associated with increased nutrient reductions. Improved reporting and enhanced crediting allow computer simulations to show a more accurate picture of the pollution entering rivers and streams from the agricultural sector.
By incorporating the best available data into our computer simulations, we gain a more accurate picture of pollution in the watershed. This gives us a better understanding of the actions that are needed to restore water quality in our work toward an environmentally and economically sustainable watershed.
With gleaming silos and an expansive field of grass that doubles as a concert venue, Brewery Ommegang cuts a scenic profile against the lush forested hills of bucolic Cooperstown, New York. But just across the road, a nondescript concrete building is dedicated to a brew of a different sort. You can’t see it from ground level, but climbing a set of metal stairs reveals a dark amber surface calmly bubbling, releasing a pungent but recognizable aroma.
“You can smell the beer,” says Ommegang brewery manager Joe Poliseno.
Standing directly above the 150,000-gallon aeration basin of Ommegang’s wastewater treatment plant does bring to mind the smell of skunked beer. It is the destination for a pipe that carries all the production waste from the brewery—municipal and human waste is handled differently. Like a miracle in reverse, this is where the leftovers of an alcoholic beverage are turned back into water.
While yeast is fundamental to brewing beer, different microorganisms play a central role in breaking down Ommegang’s liquid waste. The process removes almost all the nitrogen and phosphorus from the water leaving the plant, keeping excess nutrients out of the Susquehanna River and the Chesapeake Bay.
“Usually it's 99.9 percent removal [of nitrogen and phosphorus],” Poliseno says. “That's pretty amazing—we meet our regulations and far pass them.”
The fermentation that makes beer and other alcoholic beverages is an anaerobic process, meaning it has to occur in the absence of oxygen. The waste process, however, is aerobic. The large blowers deliver oxygen to an activated sludge made of living microorganisms. The sludge takes about eight days to cycle through the aeration basin’s membrane bioreactor that filters the wastewater.
The sludge is mostly bacteria but also tiny animals like rotifers and nematodes. As Poliseno describes it, he could be describing cattle rotated on fields of grass.
“All those hungry organisms will be brought right back to where the feed is so they can break down even faster, because they'll be super hungry at that point,” Poliseno says.
As the bacteria eat, they grow and reproduce. The excess sludge is pressed dry and harvested as a valuable biomass that farmers spread on their fields.
With all the work being done by microorganisms, most of the people power at the plant goes to lab analyses that keep the operation running smoothly.
“I was surprised once I got into it, how much science happens here,” says Ommegang publicity manager Allison Capozza. “Brewing itself is very much kind of a combination of cooking and science.”
Capozza says that Ommegang’s location was determined in part by the fact that it is the site of a former hops farm, and also by the quality of the aquifer it sits on, which Ommegang taps with three wells.
“It’s just the most perfect water you could hope for, for beer,” Capozza says, standing on the edge of the grass. “For us, from a business standpoint it’s a no-brainer that we do everything we can to protect the water, because beer is 90 to 95 percent water.”
To view more photos, visit the Chesapeake Bay Program’s Flickr page
Photos and text by Will Parson
Representatives from states across the Bay region recently signed a cooperative accord that will help reduce the amount of nitrogen flowing from onsite wastewater systems into local waterways.
At the Chesapeake Bay Program office last week, representatives from Delaware, Maryland, Pennsylvania, Virginia and West Virginia signed a Memorandum of Cooperation to share data related to the performance of advanced pretreatment technologies for “onsite wastewater treatment systems,” often called septic systems. Pretreatment of wastewater allows for the removal of potentially harmful pollutants such as nitrogen—but these technologies are often costly, and their approval takes time. Under the arrangement, information-sharing across states will help expedite the approval and deployment of these technologies, as well as offer cost savings to manufacturers and consumers.
Onsite septic systems account for less than five percent of the nutrients flowing to the Bay; advanced pretreatment technologies are expected to reduce nitrogen from these systems by at least 50 percent, as compared to conventional systems. Improvements in wastewater treatment will help achieve the clean water goals of the new Chesapeake Bay Watershed Agreement, which encompasses the Chesapeake Bay Total Maximum Daily Load (TMDL).
Scientists have found intersex fish in three Pennsylvania river basins, indicating hormone-disrupting chemicals are more widespread in the Chesapeake Bay watershed than once thought.
Image courtesy RTD Photography/Flickr
Intersex conditions occur when pesticides, pharmaceuticals or other chemicals disrupt the hormonal systems of an animal, leading to the presence of both male and female characteristics. The presence of intersex conditions in fish, frogs and other species is linked to land use, as the chemicals that lead to these conditions often enter rivers and streams through agricultural runoff or wastewater.
Previous samplings of fish in the region have found intersex conditions in the Potomac, Shenandoah and Susquehanna rivers, as well as lakes and ponds on the Delmarva Peninsula. On samplings conducted at 16 sites between 2007 and 2010, researchers with the U.S. Geological Survey (USGS) found intersex fish in the Susquehanna, Delaware and Ohio river basins.
According to the USGS, freshwater fish called white suckers from sample sites in the Delaware and Susquehanna river basins had a yolk precursor in their blood. Male smallmouth bass from all sample sites had immature eggs in their testes. The prevalence of intersex fish was highest in the Susquehanna river basin, which researchers attribute to the higher rate of farms—and related herbicides, pesticides and hormone-containing manure—in the area. While scientists found no relationship between the number of wastewater treatment plants in an area and the prevalence of immature eggs in fish, the severity of intersex conditions did rise at sites downstream from wastewater discharge points.
“The sources of estrogenic chemicals are most likely complex mixtures from both agricultural sources, such as animal wastes, pesticides and herbicides, and human sources from wastewater treatment plant effluent and other sewer discharges,” said fish biologist Vicki Blazer in a media release.
Upgrading wastewater treatment technologies has lowered pollution in the Potomac, Patuxent and Back rivers, leading researchers to celebrate the Clean Water Act and recommend continued investments in the sewage sector.
Introduced in 1972, the Clean Water Act’s National Pollutant Discharge Elimination System permit program regulates point sources of pollutants, or those that can be pinpointed to a specific location. Because wastewater treatment plants are a point source that can send nutrient-rich effluent into rivers and streams, this program has fueled advancements in wastewater treatment technologies. Biological nutrient removal, for instance, uses microorganisms to remove excess nutrients from wastewater, while the newer enhanced nutrient removal improves upon this process.
Researchers with the University of Maryland Center for Environmental Science (UMCES) have linked these wastewater treatment technologies to a cleaner environment. In a report released last month, five case studies show that wastewater treatment plant upgrades in Maryland, Virginia and the District of Columbia improved water quality in three Chesapeake Bay tributaries.
The link is clear: excess nutrients can fuel the growth of algae blooms, which block sunlight from reaching underwater grasses and create low-oxygen dead zones that suffocate marine life. Lowering the amount of nutrients that wastewater treatment plants send into rivers and streams can reduce algae blooms, bring back grass beds and improve water quality.
In New Insights: Science-based evidence of water quality improvements, challenges and opportunities in the Chesapeake, scientists show that new technologies at Baltimore’s Back River Wastewater Treatment Plant led to a drop in nitrogen concentrations in the Back River. Upgrades at plants in the upper Patuxent watershed led to a drop in nutrient concentrations and a resurgence in underwater grasses in the Patuxent River. And improvements at plants in northern Virginia and the District lowered nutrient pollution, shortened the duration of algae blooms and boosted underwater grass growth in the Potomac River.
Image courtesy Kevin Harber/Flickr
The Chesapeake Bay Program tracks wastewater permits as an indicator of Bay health. As of 2012, 45 percent of treatment plants in the watershed had limits in effect to meet water quality standards. But a growing watershed population is putting increasing pressure on urban and suburban sewage systems.
“Further investments in [wastewater treatment plants] are needed to reduce nutrient loading associated with an increasing number of people living in the Chesapeake Bay watershed,” New Insights notes.
Pollution-reducing practices can improve water quality in the Chesapeake Bay and have already improved the health of local rivers and streams, according to new research from the Chesapeake Bay Program partnership.
In a report released today, several case studies from across the watershed show that so-called “best management practices”—including upgrading wastewater treatment technologies, lowering vehicle and power plant emissions, and reducing runoff from farmland—have lowered nutrients and sediment in local waterways. In other words, the environmental practices supported under the Clean Water Act, the Clean Air Act and the Farm Bill are working.
Excess nutrients and sediment have long impaired local water quality: nitrogen and phosphorous can fuel the growth of algae blooms and lead to low-oxygen “dead zones” that suffocate marine life, while sediment can block sunlight from reaching underwater grasses and suffocate shellfish. Best management practices used in backyards, in cities and on farms can lower the flow of these pollutants into waterways.
Data collected and analyzed by the Bay Program, the University of Maryland Center for Environmental Science (UMCES) and the U.S. Geological Survey (USGS) have traced a number of local improvements in air, land and water to best management practices: a drop in power plant emissions across the mid-Atlantic has led to improvements in nine Appalachian watersheds, upgrades to the District of Columbia's Blue Plains Wastewater Treatment Plant have lowered the discharge of nutrients into the Potomac River and planting cover crops on Eastern Shore farms has lowered the amount of nutrients leaching into the earth and reduced nitrate concentrations in groundwater.
“In New Insights, we find the scientific evidence to support what we’ve said before: we are rebuilding nature’s resilience back into the Chesapeake Bay ecosystem, and the watershed can and will recover when our communities support clean local waters,” said Bay Program Director Nick DiPasquale in a media release.
But scientists have also noted that while we have improved water quality, our progress can be overwhelmed by intensified agriculture and unsustainable development, and our patience can be tested by the “lag-times” that delay the full benefits of restoration work.
“This report shows that long-term efforts to reduce pollution are working, but we need to remain patient and diligent in making sure we are putting the right practices in place at the right locations in Chesapeake Bay watershed,” said UMCES President Donald Boesch in a media release. “Science has and will continue to play a critical role informing us about what is working and what still needs to be done.”
UMCES Vice President for Science Applications Bill Dennison echoed Boesch’s support for patience and persistence, but added a third P to the list: perspiration. “We’ve got to do more to maintain the health of this magnificent Chesapeake Bay,” he said.
“We’ve learned that we can fix the Bay,” Dennison continued. “We can see this progress… and it’s not going to be hopeless. In fact, it’s quite hopeful. This report makes a good case for optimism about the Chesapeake Bay.”
The Chesapeake Bay watershed is home to more than 17 million people, each of whom is reliant on water. But as populations grow and communities expand, we send pollutants into our rivers and streams, affecting every drop of water in the region. How, then, do so many of us still have access to clean water? The answer lies within wastewater treatment plants.
One plant, in particular, plays a pivotal role in the region’s water quality. Located in Washington, D.C., the Blue Plains Wastewater Treatment Plant has served the D.C. metropolitan area since 1983. The plant receives 40 percent of its flow from Maryland, 40 percent from the District and 20 percent from Virginia. With the capacity to treat 370 million gallons of sewage each day, it is the largest wastewater treatment plant in the world and the only one in the nation to serve multiple states.
Recently, the District of Columbia Water and Sewer Authority—also known as DC Water—made technological upgrades to Blue Plains. Evidence shows these upgrades have already accounted for reductions in nutrient pollution and a resurgence in the upper Potomac River’s bay grass beds. Indeed, putting new wastewater treatment technology in place is a critical step toward meeting the pollution limits established in the Chesapeake Bay Total Maximum Daily Load. As of 2012, 45 percent of the watershed's 467 wastewater treatment plants had limits in place that met water quality standards.
Because of spatial constraints, many of upgrades planned for Blue Plains will focus on intensifying the wastewater treatment process. According to Sudhir Muthy, innovation chief for DC Water, the more concentrated the purification process is, the more energy efficient the plant can be.
For decades, the philosophy behind wastewater treatment plants has been to imitate those clean water processes that you might see in natural systems. Lately, there has been a shift in thinking about how wastewater is treated. Murthy explains: “Now, more attention is given to using the energy created within the treatment process to run the plant. [For example,] carbon has a lot of energy and is created during the treatment process. We are trying to harness [carbon’s] energy to help the plant run in a more energy-efficient way. We are now asking: How do we optimize the use of energy within the wastewater treatment process?”
Blue Plains hopes to become energy neutral in 10 to 15 years, and upgrades to reduce pollution and save energy will continue for years to come. A new tunnel will allow both sewage and wastewater to flow from the District to the plant, where it will be treated to reduce the flow of polluted runoff into the Potomac River. And a new process will recycle “waste” heat to “steam explode” bacterial sludge, turning it into a biosolid that can be mixed with soil, used as fertilizer and generate extra revenue.
“All processes use energy,” Muthy said. “But if you can find ways to offset or recycle that energy use, then you can move towards being more efficient.”
Innovations in wastewater treatment are proving effective at removing nitrogen from our waste before it is returned to rivers and streams, according to a panel of experts convened by the Chesapeake Bay Program’s Scientific and Technical Advisory Committee (STAC).
In a report released last week, STAC concludes that exploring and adopting these new technologies could help the 467 wastewater treatment plants across the watershed better respond to development pressure and continue to reduce nutrient pollution and restore water quality in the Chesapeake Bay.
Three decades ago, wastewater treatment plants and combined sewer overflows were the second biggest source of nitrogen loads to the Bay. Excess nitrogen and phosphorous can fuel the growth of harmful algae blooms that block sunlight from reaching underwater grasses and rob water of the oxygen that aquatic species need to survive. But, since the mid-1980s, advancements in nutrient reduction technologies have allowed wastewater treatment plants to reduce their nutrient loads to our waterways: between 1985 and 2012, nitrogen loads to the Bay from wastewater discharges dropped 52 percent.
A number of these new technologies put hungry microbes to work, as algae or bacteria feed on the nitrogen and phosphorous in our waste. While research in this area is still evolving, it’s possible that these technologies could also work to transform the harmful pharmaceuticals that have increasingly appeared in our wastewater over the past few decades.
Read more about wastewater treatment technologies.
After eleven years, $40 million and more than 16,000 linear feet of pipe, West Virginia is set to bring a new wastewater treatment plant online and make huge cuts to the pollution it sends into the Chesapeake Bay.
Under construction in West Virginia’s Eastern Panhandle, the Moorefield Wastewater Treatment Plant will replace four existing plants with one new system, marking a significant milestone in the headwater state’s efforts to curb pollution and improve water quality. Expected to go into operation this fall, the plant will remove 90,000 pounds of nitrogen and 93,000 pounds of phosphorous from West Virginia wastewater each year.
Funded by a range of sources—including the West Virginia Economic Development Authority, the West Virginia Department of Environmental Protection and the U.S. Environmental Protection Agency (EPA)—the new plant is heralded as evidence that thoughtful planning and forward-thinking—especially where pollution regulations are concerned—can help a community move toward conservation and environmental change.
In the 1990s, the hundreds of wastewater treatment plants that are located across the watershed could be blamed for more than a quarter of the nutrient pollution entering the Bay, as the plants pumped water laden with nitrogen and phosphorous into local rivers and streams. Such an excess of nutrients can fuel the growth of algae blooms that block sunlight from reaching underwater grasses and, during decomposition, rob the water of the oxygen that aquatic species need to survive.
But in the last decade, technological upgrades to wastewater treatment plants have surged, and the pollution cuts that result mean these plants now contribute less than 20 percent of the nutrients still entering the Bay.
According to Rich Batiuk, Associate Director for Science with the EPA, the uptick in upgrades can be attributed to a number of factors.
“Wastewater treatment plants have always been regulated,” Batiuk said. “But [until the last decade], there wasn’t the science or the political will or the … water quality standards that could drive the higher levels of wastewater treatment that result in lower levels of nitrogen and phosphorous flowing into the watershed.”
As the science behind wastewater engineering has improved and the incentives for implementing upgrades have grown, more plants have begun to make changes. Some implement a “zero discharge” plan, using nutrient-rich effluent to feed agricultural crops rather than excess algae. Others—like the Moorefield plant—expose wastewater to nutrient-hungry microbes that feed on nitrogen and phosphorous; the resulting sludge, modified without the addition of chemicals, can be turned into compost rather than fodder for the local landfill.
Such modern upgrades to otherwise aging infrastructure have been celebrated as a boon for local communities and the wider watershed. While the Moorefield plant will, in the end, curb pollution into the Bay, it will first curb pollution in the South Branch of the Potomac River, into which it sends its effluent.
"The South Branch of the Potomac is a unique place,” Batiuk said. “People fish there, they swim there. This new plant helps more than the Chesapeake Bay.”
And Moorefield residents—including the Town of Moorefield Public Works Director Lucas Gagnon—plan to witness this local change firsthand.
“The residents in this area are aware of the Chesapeake Bay and its needed [nutrient] reductions,” Gagnon said. “But the biggest benefit for the local folks will be the reduction of nutrients in local waterways.”
“There are many people that fish and boat the South Branch,” Gagnon continued. “When this plant goes online, the water quality will be greatly enhanced, and they will have a much cleaner, better river to enjoy.”
Maryland will provide more than $19 million in grants to reduce nutrient pollution to the Chesapeake Bay and its rivers by upgrading technology at four wastewater treatment plants in the state. Upgrading wastewater treatment facilities to remove more nitrogen and phosphorus from treated sewage is a critical part of meeting Bay cleanup goals.
The four facilities that will be upgraded are:
Biological nutrient removal (BNR) uses microorganisms to remove nitrogen and phosphorus from wastewater during treatment. Wastewater treated at facilities using BNR contains less than 8 milligrams per liter (mg/l) of nitrogen. Enhanced nutrient removal (ENR) improves upon the nutrient reductions achieved through BNR. Wastewater treated at facilities using ENR contains 3 mg/l of nitrogen and 0.3 mg/l of phosphorus.
Funding for the upgrades comes from Maryland’s Bay Restoration Fund – also known as the “Flush Fee.” To learn more about wastewater treatment plant upgrades in Maryland, visit the Maryland Department of the Environment’s website.
A $2.6 billion project in Washington, D.C., will nearly eliminate combined sewer overflows (CSOs) to Rock Creek and the Anacostia and Potomac rivers, helping to improve the Chesapeake Bay’s health.
The Clean Rivers Project, led by the District of Columbia Water and Sewer Authority (DC Water), is the largest construction project in the District since Metro was built.
Combined sewer overflows occur during heavy rainstorms, when the mixture of sewage and stormwater cannot fit in the sewer pipes and overflows to the nearest water body. CSOs direct about 2.5 billion gallons of sewage and stormwater into Rock Creek and the Anacostia and Potomac rivers in an average year.
The Clean Rivers Project consists of massive underground tunnels to store the combined sewage during rainstorms, releasing it to the Blue Plains wastewater treatment plant after the storms subside. The first, and largest, tunnel system will serve the Anacostia River.
Visit DC Water’s website for more information about the Clean Rivers Project.
Image courtesy Daniel Lobo/Flickr
Maryland will provide more than $29 million in grants to upgrade wastewater treatment plants and septic systems, improve sewer systems, and restore stream banks to reduce pollution to the Chesapeake Bay and its rivers.
As much as $8.9 million will go toward Bay Restoration Fund grants to upgrade septic systems with nitrogen-reducing technology. Traditional septic systems do not remove nitrogen, instead delivering about 30 pounds of the pollutant each year to groundwater. Upgraded septic systems reduce nitrogen pollution discharges by half.
The La Plata wastewater treatment plant and the Broadneck water reclamation facility will both receive Bay Restoration Fund grants to implement Enhanced Nutrient Removal. After the upgrades, the facilities will reduce their nitrogen discharge by 62.5 percent. The La Plata wastewater treatment plant will receive $8.8 million and the Broadneck water reclamation facility will receive $7.5 million.
Other funded projects include:
Maryland Gov. Martin O’Malley has signed an executive order to study septic system use in the state and find out how much pollution the on-site wastewater systems contribute to the Chesapeake Bay and its rivers.
The executive order forms a task force that includes representatives from science, business, government, agriculture and environmental advocacy communities.
The task force will review, study and make recommendations on a variety of septic and growth-related issues, including:
Approximately 411,000 Maryland households are currently on septic systems. During the next 25 years, new developments using septic systems are expected to account for 26 percent of growth in Maryland, but 76 percent of new nitrogen pollution. Maryland must reduce nitrogen pollution by 21 percent by 2020 to comply with the EPA's Bay pollution diet.”
"There's greater recognition now for the societal costs of sprawl development on septic,” said Governor O’Malley. “Continuing down the same path will undercut the progress we’ve made on restoring the health of the Chesapeake Bay and will overburden our farmers and other industries that are making changes to limit pollution in our waterways."
The task force will report its findings by December 1.
For more information about septic systems and pollution, view this presentation given by Gov. O’Malley to the Maryland General Assembly in March.
West Virginia will invest $6 million annually for 30 years toward wastewater treatment plant upgrades that will reduce nutrient pollution to the Potomac River and the Chesapeake Bay.
The money, which will come from excess state lottery funds, will fund about $85 million in bonds that will help pay for upgrades. The funding will cover about 40 percent of the expected cost for the upgrades.
The upgrades will help West Virginia meet new pollution-reduction goals that are part of the federal pollution diet for the Chesapeake Bay and its rivers. West Virginia has 13 wastewater facilities that need to be upgraded to meet nutrient limits.
Acting Gov. Earl Ray Tomblin signed the bill into law on April 6.
The Blue Plains Advanced Wastewater Treatment Facility in Washington, D.C., will discharge 3.8 million fewer pounds of nitrogen each year by 2015 as the result of a renewed operating permit issued by the U.S. Environmental Protection Agency (EPA).
The reissued permit will reduce by 45 percent the amount of nitrogen that the Blue Plains wastewater facility – the largest single point source of nitrogen pollution in the Chesapeake Bay watershed – discharges to the Potomac River and the Bay.
“These reductions are critical to protecting the health of the Chesapeake Bay as well as the Potomac River,” said Shawn Garvin, the EPA’s mid-Atlantic regional administrator. “By significantly reducing nitrogen pollution from the Blue Plains plant, we’re taking a major step on the road to restoring the Bay for future generations.”
Nitrogen is a type of nutrient that contributes to cloudy, polluted waters in the Bay and its rivers. Excess nitrogen fuels the growth of dense algae blooms that rob fish, crabs, bay grasses and other Bay life of sunlight and oxygen.
Blue Plains is the largest advanced wastewater treatment facility in the world, treating wastewater for approximately 1.6 million people in Washington, D.C., Montgomery and Prince Georges counties in Maryland, and Fairfax and Loudoun counties in Virginia.
Under the permit renewal, DC Water will reduce nitrogen discharges from 8.5 million to 4.7 million pounds each year by upgrading the Blue Plains facility. Modifications are to be completed by July 2014 so that pollution reductions can be fully achieved in 2015.
This action is part of a larger effort by the EPA and the Bay states to control nitrogen and phosphorus discharges from more than 483 significant wastewater facilities across the Bay watershed. By 2015, most of these facilities will be upgraded to meet more stringent permits that will reduce an additional 11 million pounds of nitrogen and 100,000 pounds of phosphorus to the Bay.
During the past 25 years, Bay Program partners have made significant progress reducing nutrient pollution from wastewater facilities. Pollution from wastewater has dropped 55 percent since 1985.
In comparison, agricultural pollution has decreased 31 percent and pollution from cities and suburbs has increased 15 percent since 1985.
For more information about the Blue Plains upgrade, visit the EPA’s website.
Welcome to the latest installment of the BayBlog Question of the Week. Each week we take a question submitted through the Chesapeake Bay Program website and answer it here for all to read.
This week’s question comes from Matt:
“How are limits at wastewater treatment plants set? Is it based on water quality standards or limit of technology?”
Ultimately, nutrient discharge limits for wastewater treatment plants in the Chesapeake Bay watershed are set to improve water quality, but many plants face limitations because of technological capabilities. Nutrient discharge from wastewater treatment facilities is one of the biggest causes of poor water quality in the Bay. Because of this, the Chesapeake Bay Program has been working to reduce nutrient pollution from these sources since 1985.
In 2005, the Chesapeake Bay jurisdictions introduced a new permitting process limiting the amount of nitrogen and phosphorous that the watershed’s 483 major wastewater treatment plants could discharge. These limits meant that most facilities had to make major renovations and upgrades to include biological nutrient removal and enhanced nutrient removal technologies.
In the biological nutrient removal (BNR) process, microorganisms remove nitrogen and phosphorous from wastewater during treatment. The wastewater treated in this process contains less than 8 milligrams per liter (mg/l) of nitrogen. Enhanced nutrient removal improves upon the BNR process, with wastewater treated at these plants containing 3 mg/l of nitrogen and 0.3 mg/l of phosphorous.
Some of those facilities that are required to meet stricter limits but cannot afford more advanced upgrades still have options. Nutrient trading programs have been implemented in Pennsylvania and Virginia for precisely that reason. These programs encourage facilities to invest in upgrades with greater nutrient reductions and then sell their excess nutrient credits to other facilities. This provides plants a cost-effective way to meet the limits imposed on them to improve water quality if they are lacking the technological advances.
And remember, you can do your part to help wastewater treatment plants reduce nutrient discharge too. Two easy steps are conserving your water so the facilities have less water to treat and switching to low- or no-phosphorous dish detergents. For more information, check out our Wastewater Treatment page.
Do you have a question about the Chesapeake Bay? Please send it to us through our web comment form. Your question might be chosen for our next BayBlog Question of the Week!
Virginia has received $80.2 million through the American Recovery and Reinvestment Act to upgrade and improve wastewater treatment facilities throughout the state, which will help lessen a major source of nutrient pollution to the Chesapeake Bay and its rivers.
The funding will help Virginia and its local governments install nutrient-reducing technology at many wastewater treatment plants, as well as eliminate overflows of raw sewage to local rivers throughout the state, including from Combined Sewer Overflow (CSO) systems in Lynchburg and Richmond.
Approximately one-fifth of nutrient pollution to the Bay comes from wastewater. All seven jurisdictions in the Bay watershed – Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia and the District of Columbia – are currently working to reduce pollution from wastewater by installing nutrient-reducing technology at major wastewater treatment facilities.
“We have worked hard to restore the health of the Chesapeake and all Virginia waters, but also we know that we have much more to do,” said Virginia Gov. Timothy Kaine. “These funds will significantly help us advance our work to reduce pollution from sewage treatment plants.”
The funding will also be used to implement wastewater reuse projects, alternative energy use at wastewater treatment plants, and address public health problems in areas not currently served by centralized sewage systems.