The cry “Save the Bay” has been heard in the Chesapeake region for decades, aimed at motivating citizens and policymakers alike. But a recent study is emphasizing a less publicized angle: Benefits of the cleanup will extend far beyond the Bay itself. According to researchers, the regionwide economic value of those benefits could top $129 billion per year.

The study, Ecosystem Service Benefits of a Clean Chesapeake Bay, was published in May 2016 in Coastal Management. The research was conducted by Spencer Phillips, a consulting economist and lecturer at the University of Virginia, and Beth McGee, senior scientist at the Chesapeake Bay Foundation, a nonprofit organization dedicated to restoring the Chesapeake.

Ecosystem services are functions provided by natural systems such as forests, wetlands and floodplains that benefit human well-being. For instance, canopies of trees filter air pollution while their root systems reduce nutrient and sediment pollution flowing into waterways. When the ecosystem isn’t functioning well or is out of balance with population demands, humans have to design systems to help or replace those services — and engineered solutions come with a price tag.

Phillips and McGee focused on eight ecosystem services: food production, climate stability, air pollution treatment, a stable water supply, water regulation (flood prevention), waste treatment (nitrogen removal), aesthetics and recreation.

The benefits of ecosystem services have been discussed and studied since the 1960s. But McGee said she is not aware of any previous studies like this one, which looked at a broad set of services specific to the Chesapeake region and assigned them a dollar value.

“That’s the void we were filling,” McGee said.

Their calculations indicate that the present value of ecosystem services for the region is approximately $107.2 billion per year. In other words, natural features such as forests and floodplains provide benefits such as pollution filtration, flood reduction, clean drinking water and other services that would require $107.2 billion to replace, if those services were no longer provided by natural systems. (All value estimates in the study are based on 2013 dollars.)

Phillips and McGee compared the baseline value of $107.2 billion with two different scenarios.

For the first scenario, they assumed that pollution reduction programs, as well as population and land use trends, would continue with “business as usual.” In this scenario, most pollution reduction projects would be driven by longstanding regulations and the requirements of existing permit processes. It would not include the more aggressive pollution reduction plans resulting from the federally mandated Chesapeake Bay Total Maximum Daily Load and the state watershed implementation plans, or WIPs, created to support it.

“The assumption is that progress for things that are regulated, like MS4 (stormwater) permits and point sources, will continue, because they are being driven by more than the WIPs,” McGee said. “They would happen even if the WIPs go away.”

But even with those efforts under way, Phillips and McGee found that the region will face a loss of ecosystem services. That’s because, based on Chesapeake Bay Program projections of land use change and pollution loads, more natural areas would be converted to other uses. Also, the conditions of forests, wetlands and streams would deteriorate.

In all, the “business as usual” results in a loss of ecosystem services worth $5.6 billion annually. That would reduce the total regional benefits to $101.5 billion per year beginning in 2025.

For the second scenario, Spencer and McGee assumed that actions for meeting the TMDL would be fully implemented across the region at state and local levels, and that, collectively, these actions would reduce the pollution loads to the required levels by 2025.

In this scenario, more acreage is given to forests and wetlands, stream buffers are protected; and management practices help the ecosystem functions perform at a higher level.

As a result, ecosystem functions improve and their value rises. Spencer and McGee estimate that achieving the goals of the TMDL would deliver ecosystems services with an annual value of $129.7 billion — an increase of more than $22.5 billion or approximately 21 percent per year compared with the estimated baseline value.

“For me, the big takeaway message is that if you implement these things, all these other benefits are out there, from reduced flooding to recreation and tourism, to protecting your water supply, shading urban areas and reducing air pollution,” McGee said. “And, when you think about the price tag associated with the cleanup, this puts it in context.”

The Chesapeake Bay may, in fact, be “saved” under this scenario, but the other areas that also have the most to gain are those farthest from the Bay, in the western and northern parts of the watershed with more rural, mountainous landscapes. The report states that, “The majority of the benefits of implementing the Blueprint [TMDL] will accrue to “upstream” habitats rather than to the open water habitat that includes the Chesapeake Bay and its tidal rivers.”

A major reason for this is that well-managed forests, especially where they shelter streams and rivers, provide the greatest range of benefits.

“Forests provide a lot of services, from carbon storage and air pollution reduction and water pollution reduction to shading. Forest and wetlands, on a per acre basis, provide the most value,” McGee said.

Adding up the benefits, McGee acknowledged that the economic benefits of ecosystem services don’t translate into cost savings in one lump sum to any one source.

Some benefits, like enhanced tourism based on a healthy fishery, are more tangible than others. Others are less visible, such as dollars that need not be spent to repair flood damage and eroding streambanks, or fewer trips to the hospital for people who are especially vulnerable to air pollution.

“Those are cost savings that you might not see directly, but are very real,” McGee said.

Efforts to quantify the economic benefits of reducing pollution are also under way at the Chesapeake Bay Program. The program is a partnership between state and federal governments that coordinates major elements of the Chesapeake cleanup effort.

In 2017, the Bay Program’s Scientific and Technical Advisory Committee will begin identifying best management practices for which economic benefits have been well-documented. Their goal is to add that information to a computer system called the Chesapeake Assessment Scenario Tool, or CAST.

Local governments use CAST to evaluate pollution reduction practices that could be used in local settings. CAST calculates the expected amount of pollution reduction from a given project, as well as its cost.

McGee wants to see a projection of economic benefits added to the mix of factors that local governments consider, and hopes that it will provide a new context for ongoing discussions about the shared costs of cleaning up the Bay.

Nature at Work

Ecosystem services are the benefits that people derive from nature. Analysts describe a range of categories, from the production benefits of food and timber to pollution reduction and recreational benefits. Here are some examples:

  • Water supply: Forests, wetlands, streams and open space all play a role in supplying surface water and recharging the region’s aquifers. They also provide natural filters for sediment, nutrients and other pollutants in the water. This leads to cleaner drinking water and lower water treatment costs for residential and industrial users.
  • Water regulation: Maintaining a steady flow of water in rivers and streams depends largely on the ability of the land to absorb and store water. Impervious surfaces like roads, rooftops and sidewalks prevent rain from soaking into the ground. Instead, the rainwater surges through storm drains and stream channels, increasing floods and eroding streambanks. With less water stored in and along streams, streamflows in these same locations can be low or dry at other times of the year.
  • Reducing air pollution: Healthy forests and wetlands are able to absorb and process airborne pollutants, which in turn provides public health benefits. According to the U.S. Environmental Protection Agency, the estimated value of air pollution reductions derived from a Lancaster, PA, green infrastructure plan is more than $1 million per year for local residents.
  • Climate stability: Land cover influences the stability of air temperature and has a direct impact on heating and cooling costs. In urban areas, trees and other vegetation reduce the concentration of high temperatures known as the “heat island” effect. According to the study, Ecosystem Service Benefits of a Clean Chesapeake Bay, shaded houses can have 20–25 percent lower annual energy costs than the same houses without trees.