By Nick DiPasquale & Joel Dunn in Chesapeake Bay Journal
The Chesapeake Bay restoration and conservation movement is nearly 50 years old. What started with advocacy and litigation, essential to galvanize action, has now fully entered the implementation and quantification phase.
Partners throughout the watershed are focused on delivering results on-the-ground.
We are witnessing the dawn of a new era for our society and the Bay movement: one where we regularly employ advanced technology and intense collaboration to move from an effort-based initiative to a results-oriented community.
There is so much to celebrate regarding progress in the restoration and protection of the Chesapeake ecosystem.
Water clarity is the best it has been in decades. Rockfish, oysters and blue crab populations are rebounding, underwater grasses hit record levels for the third year running and we continue to conserve critical lands and enhance public access.
Other than the land conservation and public access results, approximately 60 percent of these improvements can be attributed to “point source” or end-of-pipe solutions, primarily upgrades at major wastewater treatment plants like Blue Plains.
If we are to succeed in meeting our water quality goals, the next decade of actions will need to focus on “nonpoint source” pollution, such as farm and urban runoff, which will be more difficult to tackle.
Fortunately, we have entered the age of data-driven conservation.
Cloud computing, geographic information systems and remote sensing have completely changed the realm of the possible and allowed us to pinpoint nonpoint source pollution as well as opportunities for precise intervention.
As a result, the time has come for organizations and agencies to be evaluated on measurable results that can be directly tied to their activities.
As Joe Whitworth eloquently points out in his book, Quantified: Redefining Conservation for the Next Economy, this shift will revolutionize public, private and philanthropic investments in the environment by changing their focus to quantified outcomes.
And thank goodness, because these new approaches need to become the norm, not the exception, in order to address the severity of our environmental problems.
Since its establishment in 1983, the Chesapeake Bay Program has prided itself on using science and consensus to make ecosystem restoration and conservation decisions.
Rapid advancements in geographic information systems have helped us understand the landscape and revolutionized how we monitor, model, evaluate and even govern the Chesapeake Bay.
Every version of the Bay Program’s watershed model, now in its sixth iteration, has used extensive data for best management practices, land use/cover, point sources, septic systems, federal population and agricultural census data, and other sources of pollution information.
These linked models also incorporate precipitation, meteorological, soil and elevation data and are linked to national airshed models and land use change models.
These environmental simulations give us an unprecedented understanding of how the watershed works and serve to estimate pollution loadings, based on land use patterns, and pollution reductions, stemming from the implementation of pollution control measures.
The Bay Program partnership is halfway through the implementation of the Chesapeake Bay Total Maximum Daily Load, or “pollution diet.”
As part of the process, the partners agreed to conduct a Midpoint Assessment to determine whether the jurisdictions have achieved 60 percent of the pollution reductions required to meet their pollution allocation by the 2025 deadline.
In recent years, the ability to collect, manage and analyze mountains of data has improved exponentially.
Important Bay model improvements include incorporating new information on climate impacts, such as increased water temperatures and sea level rise; newly approved best management practices, such as land conservation and restoring oyster reefs; phosphorous-saturated soils; lag times that are due to contaminated groundwater; and water quality data and monitoring trends.
One of the largest changes in the Midpoint Assessment is the resolution at which the model runs. Earlier versions relied on 30-meter resolution land cover data, which was the state of the art at the time.
At that level of resolution, each pixel represented about a quarter acre on the ground, and sources of pollution and the loading rates associated with various land uses had to be generalized at the county level. This could result in erroneous or inaccurate land use designations, misidentification of pollution sources and other anomalies.
In 2011, the Bay Program recognized and acknowledged the need to make improvements in the model and its data sources to more accurately simulate the watershed.
The Chesapeake Conservancy, working with contractors for the Virginia Geographic Information Network, in collaboration with the Bay Program’s Land Use and Modeling Work Groups, created high-resolution land cover data at a 1-meter level for the entire watershed.
This new classification provides 900 times the amount of information and greater accuracy compared with conventional 30-meter resolution data.
In addition, the Land Use Work Group obtained updated land use information from more than 80 percent of the local governments in the watershed.
The combination of high-resolution land cover data with updated land use information provides a much more accurate and precise representation of what is occurring on the land throughout the watershed. In short, we have much better data.
With forthcoming new high-resolution data sets, the Bay Program will be able to evaluate land use changes at 1 meter over time to determine whether the jurisdictions will need to offset any increases in nutrient and sediment loadings from new sources or increases from existing sources.
The Conservancy is working with Microsoft Research and Esri to pioneer a technique that leverages artificial intelligence to decrease the amount of time it takes to update the watershed’s land cover data.
The high-resolution land cover data also creates an opportunity to identify where conservation and restoration actions are needed, such as defining the extent of riparian forest buffers and urban tree canopy.
Already, the conservancy has used this data, along with light detection and ranging data — which provides elevation information — to produce an inventory of roadside ditches throughout two counties in Pennsylvania, a significant but unaccounted-for source of nutrient and sediment pollution.
There are plans to expand the analysis watershedwide.
The conservancy is also leveraging the new land cover and elevation data in tools that allow local partners to incorporate it into their planning efforts.
For example, they developed a stormwater planning tool for local governments in York County, PA, that are subject to the Municipal Separate Storm Sewer System stormwater regulations.
This tool is tied to the Chesapeake Assessment Scenario Tool and allows local governments to quickly and easily identify potential stormwater projects at the parcel level and calculate the amount of pollution reduction they would need to achieve to meet their obligations under the Bay’s pollution diet.
The conservancy is also developing new capabilities for determining the most effective placement for agricultural best management practices — not just on a single field, but across entire watersheds.
This allows jurisdictions and federal grant funding agencies to focus scarce financial and technical resources where they will get the greatest pollution reductions at the least cost. Importantly, these tools also create greater flexibility to work with landowners to find an appropriate solution that creates environmental benefits without placing an undue burden on their operations.
The Chesapeake Bay restoration movement has made great strides. Together, we have tackled large problems, such as upgrading wastewater treatment plants to such a degree that they have already met their 2025 pollution reduction goals.
But it is clear that we will not reach water quality standards by using the same approaches and practices that have allowed us to get to this point. Now we need to face the most herculean of all tasks-- working acre by acre on targeted restoration projects. The time for data-driven precision conservation has arrived, and the data is here to support it.
Nick DiPasquale is the former director of the Chesapeake Bay Program
Joel Dunn is the president and CEO of the Chesapeake Conservancy
(Reprinted from the Chesapeake Bay Journal.)
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