We have been collecting water quality data on Antipoison Creek for about 11 months now, sampling for nitrate-nitrites (NO23), phosphates (PO4), ammonium (NH4), and chlorophyll. Our data collection extends from last September to this May (with sampling ongoing). Last month, Gary, Libby and I visited with Dr. Lora Harris, an associate professor at the University of Maryland’s Center for Environmental Science (UMCES), who specializes in systems ecology and ecosystem modeling, to get input on how to analyze our water quality data.
Dr. Harris gave us several suggestions, one of which was to create a Nitrogen Loading Model (NLM) for Antipoison Creek, to determine if the creek is primarily fed by nitrogen coming in from the Chesapeake Bay, or from the watershed (land-based activity and runoff, groundwater leaching, and atmospheric deposition). Harris described the NLM as a type of box model, showing inputs and outputs in and from a watershed. (See Figure 1, from the NLM instruction manual below).
The Nitrogen Loading Model, created by Mark J. Brush (VIMS), Lora A. Harris (UMCES), Juliette C. Giordano (VIMS), and Joanna K. York (UDEL) allows a user to put in data on land use and activity in a specific watershed- for us, Antipoison Creek. The model pulls in miscellaneous information on the watershed, such as atmospheric deposition, loads from point sources, and surface area of the creek. It also pulls in data on non-agricultural and agricultural land cover, as well as the fertilization rate and agricultural yield of each crop grown in the watershed.
Using a mix of applications including a GIS operating system (QGIS) and GoogleEarth, as well as a number of sources on Antipoison Creek and Lancaster County, we came up with estimates for the needed parameters. Once all the inputs were entered, and the model generated kilograms of nitrogen for groundwater input, wastewater input, direct atmospheric deposition onto water surface, and a total annual load of nitrogen (kg) entering the watershed, we contacted Dr. Brush to discuss our procedure and results.
Now that we have an annual watershed load for nitrogen to the estuary, we must determine if Antipoison Creek has a greater flux of nitrogen coming from the watershed and emptying out into the Bay, or if the Bay is primarily feeding the creek with an influx of nitrogen.
We will be working with Dr. Brush on this next step, as well as a more in-depth paper to share our work on the NLM model.
Source: Brush, M.J., L.A. Harris, J.C.P. Giordano, and J.K. York. 2015. Delmarva Coastal Bays Nitrogen Loading Model. Virginia Institute of Marine Science, Gloucester Point, VA. Available at: http://www.vims.edu/research/departments/bio/programs/semp/models/index.php.
Each year, the University of Maryland Center for Environmental Science, the University of Michigan, and the National Ocean and Atmospheric Association collaborates on models predicting the size of the dead zone that will be found in the main stem of Bay over the summer months. Using USGS data on nutrient and sediment loads entering the Bay from the first half of this year, the models can pretty accurately predict how big this dead zone will be. This year’s prediction: the dead zone will be “slightly smaller-than-average.”
Please see the Chesapeake Bay Program for more information.
The Potomac Conservancy has released their biennial report on the Potomac River, the second largest river draining into the Chesapeake Bay. The health of the Potomac River, due to its large area and population size within watershed boundaries, is very important to the health of the Bay. The Potomac Conservancy has issued the River a grade of B- in terms of overall health. Rising from a D to a C to a B- over the past ten years, the state of the Potomac River is improving. However, a number of different areas need to be addressed to continue to improve water quality in the Potomac and the Chesapeake.
Figures 1, 2, and 3 show changes to nitrogen, phosphorus and sediment loads in the Potomac from 1985 to 2014. Over this time period, there have been load reductions from these three major sources of pollution.
The improvements in overall health of the Potomac River are due in large part to reduced sediment and nutrient loads from agricultural activity and wastewater treatment plants.
Wastewater treatment facilities have undergone a number of upgrades to ensure that water discharged from facilities contains smaller concentrations of nitrogen and phosphorus. With higher standards now required by the EPA, upgrades to many wastewater treatment facilities in the watershed have contributed to cleaner waters in the Potomac River. (Between 2011 and 2015, there was a 13% increase in facilities adhering to stricter EPA standards).
Agriculture in the Potomac River watershed has likely contributed fewer nutrient loads because agricultural activity within the region is declining, as land is converted to accommodate urban sprawl. The Potomac River, which flows from Fairfax Stone, West Virginia to Point Lookout, Maryland, covers a large urban and suburban area. So, while agricultural runoff is decreasing, nitrogen and phosphorus loads in stormwater runoff from developed areas is still a major concern.
Within this report, the Potomac Conservancy grades a number of sub-indicators of river health, such as fish population, underwater grass abundance, and recreational use. These ratings are then examined together to determine overall health. While overall health of the river is improving, there are some areas that are actually doing worse, or showing no marked improvement from previous years. This is the case for water clarity and underwater grass abundance, which received a grade of C-. These two factors are important indicators of health in the Chesapeake Bay (underwater grasses provide food and habitat for marine species, and filter sediments and nutrients in the water, which can improve water clarity). Going forward, I would definitely like to see higher rates of recovery for these two indicators.
There is mixed news for the river’s fish populations. Certain species, such as shad, white perch, and smallmouth bass are experiencing population growth. The Bay’s rockfish population, however, has declined slightly over the past ten years. Many fish species are at continued risk of predation from invasive species such as the blue catfish and snakehead.
In terms of tidal water quality, certain conditions are improving, although numbers for dissolved oxygen, clarity, and chlorophyll A (a measure of algae), vary year to year. Chlorophyll A levels have declined over the last fourteen years. See Figure 4 below.
[We have been taking water samples from both the Potomac River (out of Great Falls), and Antipoison Creek, (which is just off of the Chesapeake Bay, close to where the Rappahannock River meets the Bay), and interestingly, found higher chlorophyll levels in Antipoison Creek. I’ll post more on our results later.]
There was good news for recreational land use, which has gone up since the last report. Recreational use of waterways can be an indicator of improved water quality.
Protected land area has increased, from 1.8 million acres in 2011 to 1.9 million acres in 2013. This area equates to 26.6 percent of land in the Potomac River watershed.
Concerns going forward include rates of deforestation and development in unsuitable areas, and runoff from suburban and urban regions. Agricultural areas, while declining, could still do with the enforcement of Best Management Practices (BMPs). The amount of forested buffers (streamside vegetation which reduces agricultural runoff into tributaries), received a grade of C-.
It’s important to keep in mind that the results in this report do not come from the most current data. The Potomac Conservancy gathers its information from a number of institutions, such as the EPA and the USGS. There is a couple years lag time on data for many of these sub-indicators of overall health.
Information and graph source: State of the Nation’s River 2016, Potomac River Conservancy, http://potomacreportcard.org.
Last week, I saw several Chesapeake Bay news stories referencing a Maryland Lawn Fertilizer Law. There has been a lot of discussion in recent months about agricultural application of fertilizer, and the harmful effects nutrient farm runoff has on the Chesapeake Bay Watershed. Fertilizer is also frequently applied in nonagricultural settings, (with lawn fertilizer accounting for 44% of all fertilizer sold in Maryland), and can have just as harmful an impact on the Bay (but at a smaller scale).
I took a look into the Maryland Lawn Fertilizer Law, which went into effect in 2013. This law creates limits and restrictions for lawn fertilizer application across the state, in an attempt to reduce nitrogen and phosphorus runoff into the Bay Watershed. Before 2013, there were no Maryland state laws aimed at homeowners, and other non-agricultural consumers of fertilizer. Restrictions of fertilizer use for farmers has been in place since 2001. The Maryland Lawn Fertilizer Law targets fertilizer use by not only urban and suburban homeowners, but also owners of golf courses, parks and athletic fields, and businesses.
While the law does not forbid home and business owners from applying any fertilizer, it limits what can be laid down – limits that are created based on what is strictly necessary (and determined by the University of Maryland). Excess fertilizer results in stormwater runoff, depositing phosphorus and nitrogen into the Bay watershed, which is already heavily polluted with these nutrients.
This state law overrules any preexisting county legislation in Maryland that applied to nonagricultural fertilizer use.
-Lawn fertilizers with phosphorus (unless a soil test is taken, and shows that a particular lawn is in need of phosphorus)
-Lawn fertilizers with less than 20% nitrogen that is slow release
-The application of more than 0.9 pounds of total nitrogen per 1,000 square feet
-The hiring of lawn care professionals not certified by the Maryland Department of Agriculture (penalties apply: $1000 for the first violation, $2000 for every violation after that)
-The application of lawn fertilizers during “blackout dates” (November 15 – March 1)
-The application of lawn fertilizers to any impervious surfaces
-The application of lawn fertilizers before heavy rain forecasts
-The application of lawn fertilizers within 15 feet of waterways
Is nutrient pollution trading in Maryland the answer to Bay cleanup or just another stalling mechanism? Maryland Governor Larry Hogan has proposed a new pollution trading system focused on nitrogen and phosphorus runoff. The system would allow communities, in need of upgrades to their local sewage treatment plants and stormwater runoff programs, to instead pay area farmers to pollute less. While this may result in fewer loads of nitrogen and phosphorus runoff from agricultural sources, (which is greatly needed), the plan allows urban and suburban communities to shift focus away from their own sources of pollution. The state should instead be focusing on a two-pronged approach, targeting pollution loads from agricultural and urban/suburban sources.
Agriculture is one of the leading sources of pollution to the Chesapeake Bay, but it is not the only major source. Municipal and industrial wastewater (a sector that includes sewage treatment plants), contributes 19% of the nitrogen that reaches the Bay, and 21% of phosphorus; urban and suburban runoff contributes 31% of phosphorus pollution in the Bay (National Research Council, 2011). Just last week, The Washington Post reported on a Maryland-based water treatment plant, just north of Washington, D.C., that has been polluting millions of pounds of nutrients and chemicals into the Potomac River. The Washington Suburban Sanitary Commission (WSSC), which runs the plant, from the outcome of a recent legal settlement, has agreed to make millions of dollars worth of upgrades to its outdated facility, (built in the 1960s). These upgrades are expensive, but they are long overdue, and are needed to improve water quality in the Potomac River, a major tributary of the Chesapeake Bay.
Supporters of the proposed nutrient trading program in Maryland argue that nutrient trading will allow for cleanup of the Bay, while reducing costs to communities, which might have plants that need millions of dollars worth of upgrades, like the WSSC facility . However, I would argue that nutrient trading allows half of the pollution problem to be ignored. Maryland should target both agricultural runoff and urban and suburban sources of pollution if its leaders are serious about cleaning up the Chesapeake Bay.
Virginia, West Virginia, New York and Delaware are set to receive $1 million each from the U.S. Department of Agriculture (USDA) as part of a federal effort to improve water quality in the Chesapeake Bay. Money will go toward farmers in the Bay watershed with stream access on their properties. Specifically, the money supports planting of vegetated streamside buffers on agricultural lands.
These vegetated streamside buffers, or riparian buffer zones, act as physical barriers to livestock, which might otherwise have direct access to pollute streams. Riparian buffer zones also reduce sediment and nutrient loads, running off from farmland, and entering the watershed.
The USDA is able to offer federal funds to Bay states under their Conservation Reserve Enhancement Program (CREP). According to the USDA, CREP and USDA funds (about $500 million in total), supplied to Bay states since 1996, have resulted in the planting of 7000 miles of riparian buffer zones, and “have prevented an estimated eight million tons of sediment, 16 million pounds of nitrogen, and four million pounds of phosphorus from entering the waters of the watershed.” (See http://www.usda.gov/wps/portal/usda/usdahome?contentid=2015/10/0271.xml&contentidonly=true).
The USDA CREP program is voluntary. Funds are being offered to agricultural landowners who agree to participate in planting riparian buffer zones, and require financial support.
The $4 million going to Virginia, West Virginia, New York and Delaware is a first round of funding. A second round from the USDA will likely target Maryland and Pennsylvania- states with significant amounts of agricultural runoff to the Chesapeake Bay.
Kudos to the Chesapeake Bay Foundation (CBF) for moving ahead on a major water quality issue in Virginia. This week CBF filed suit against Virginia’s Department of Environment Quality (DEQ) and the State Water Control Board over failure to enforce state regulations for livestock farmers.
One of the management practices Virginia has said it will implement to reduce water pollution in the Chesapeake Bay watershed is making sure all farmers keep their livestock out of streams and rivers through the use of fences and stream buffers. CBF has found that many Virginia livestock farmers are not implementing these management practices. This is thanks to the Virginia Pollution Abatement Permit, approved last year by the DEQ and the Water Control Board for a ten-year period. This permit does not require the state’s largest livestock farms (cattle, pig, poultry) to fence and buffer streams to which the livestock have access.
CBF’s challenge to the DEQ and the State Water Control Board, should it be upheld in court, will improve a flawed permitting process, ensure that Virginia does its part to reduce water pollution, and ultimately improve the health of the Chesapeake Bay.
Fencing off streams and rivers from livestock reduces water quality issues in the tributaries and mainstem of the Chesapeake Bay. When livestock have wading access to bodies of water, they are able to pollute streams and rivers with their waste, adding to the nitrogen and phosphorus runoff that enters the Bay. Livestock also erode stream banks, depositing sediment directly into the water, which makes its way downstream and eventually reaches the Bay.
By allowing farms to give their livestock access to streams and rivers, the DEQ and State Water Control Board are not enforcing the State Water Control Law, which calls for a reduction and prevention of water pollution. Furthermore, by not enforcing regulations that curb nitrogen, phosphorous and sediment runoff from agriculture, Virginia is violating its agreement with the EPA (in the Clean Water Blueprint) to reduce nutrient and sediment pollution entering the Bay from state waters.
The Richmond Circuit Court will hear arguments for this case this Thursday, July 2. Updates to come.
The original press release from CBF can be found here.