Wednesday, June 12, 2013

Watersheds: Preservation of Ecosystem Services Through Protection

A watershed is an area or region drained by a river, river system, or other body of water. Most of the time ridges along mountains or hills divide one watershed from another. These complex systems of land and water are very important for biological diversity and ecosystem health. Since watersheds connect and encompass terrestrial, freshwater, and coastal ecosystems, they also perform a wide variety of valuable services (8). The ecosystem health of a watershed determines how well it functions (and in turn the quality of services), among other important factors.

Figure 1: Watershed diagram (3).

Two types of ecosystems that play a crucial role in the proper functioning of a watershed are healthy forests and wetlands. Humans benefit significantly from natural services provided by these ecosystems and their respective watersheds. Some of these services include: water purification, groundwater and surface flow regulation, erosion control, and stream bank stabilization (1). In addition to these specific services, a healthy watershed can provide ecosystem services in each of the four categories: supporting, provisioning, regulating, and cultural.

If the breadth of services associated with watersheds is not enough for one to realize the utmost importance of watersheds (and their health), maybe an analysis of current (and future) global socio-political factors will paint a clear picture. Economic growth and increases in human population are leading to a higher demand for water resources, while increasing pressure on the ecosystems that provide watershed environmental services (7). Economic policies to promote agriculture have led to widespread demand for water for irrigation, and have lead to widespread clearing or modification of natural ecosystems (7). These different factors, and their ensuing growth over time, have led to degradation of watershed ecosystems and a decrease in the quality of services they provide.

Figure 2: A complete list of ecosystem services provided by healthy and functioning watersheds (9).

Regulation of public goods and services, like those provided by a watershed, are extremely difficult because there is no incentive for anyone to change the way they interact with their land. Decisions made by upstream landowners do not take into account the effect their action will have on the water quality and quantity for downstream users. This is because they’re not affected directly, so there is no incentive for them to care (2). People with this mentality create scenarios similar to the tragedy of the commons for a number of public goods/resources. What should be done to hold people accountable and ensure environmental quality is not further degraded? Varying degrees of legal framework and conservation plans are a good start.

Traditionally, regulation (usually by the government) has been the route for devising and implementing land management practices, but ideas to control negative impacts on ecosystems and biodiversity have sounded great in theory but do not translate to practical, real world, applications (7). While this practice may work for some natural resources, implementation and monitoring for compliance in relation to land-use and water resources is extremely difficult. Another option for the ensured provision of environmental resources is implementation of market-based mechanisms. This method involves making people pay for environmental services through taxes, subsidies, licenses, permits, and other relevant instruments. Basically, the environment would be monetized and people pay according to negative impacts, or lack of negative impacts. Some combination of the two methods will probably be most effective. Ultimately regulation or protection of land will be necessary for ensured provision of services, because current market mechanisms are not providing optimal levels of ecosystem services (9).

Discussing theories without applying them to a real world situation is difficult, so let’s analyze New York City’s revolutionary project that involved protecting their drinking water supply through initiatives that preserved the integrity of ecosystem services provided by their watershed. I’ll provide an overview of the many different goals of stakeholders involved so an understanding of this unique situation and the multitude of factors involved can be developed.

Over a period of almost two hundred years the City depended on one of the largest unfiltered water systems in the world. This system is known as the Catskill watershed. It spans approximately two thousand square miles (an area about the size of Delaware) with a network of 19 reservoirs and aqueducts that cut across nine counties, providing 90% of the 1.2 billion gallons of drinking water consumed every day by 9 million New Yorkers (6). Citizens of the City had invested heavily in this intricate water delivery system, but when the federal government passed the Safe Drinking Water Act in 1974 this world-class water system required more investment. Despite the watershed’s high water quality, the Safe Drinking Water Act of 1974 requires that all major surface water systems providing potable water filter this water or prove they can protect the watershed producing it (6). In the face of this federal mandate New Yorkers began to appreciate the water from this system even more, and were left with a decision to either build a filtration plant or protect the watershed (and in turn the ecosystem services provided by the system).

Figure 3: Catskill watershed (Map created by the Catskill Center for Conservation and Development, December 2005)

To build a filtration plant big enough to filter and clean the entire municipal water supply, the City would’ve needed to invest approximately $8-$10 billion (in today’s dollars) of which $6 billion would be used for construction of the facility and $250 million would be paid annually to operate this filtration plant (5). On the other hand, preservation of the watershed was estimated to cost $1.5 billion, a fraction of the cost needed to filter all the water through a protected forests in the watershed, instead of using a man-made plant to filter the City’s water supply. In light of the economic benefit associated with using the watershed’s natural processes and ecosystem services, New York City began implementing this monumental watershed preservation project in 1997 through a series of land purchases that allowed them to place these areas under protection which in turn shielded reservoirs from pollutants (5). The project/program also involved improving treatment plants and septic systems, in addition to subsidization of environmentally sound economic development. This program was, and still is, extremely unique because both economists and environmentalists embrace it. Synergy like this is rarely seen when environmental projects are being debated or implemented. It is also a great balance between economical decisions and preservation of ecosystem services provided by a vast watershed.

Despite the success experienced by the City and its residents, the people living in the watershed and on the land purchased by the government did not experience as much success. These people were still bitter from the past when the City was on a reservoir-building spree and used eminent domain to force many of these people and their relatives of their land. Despite this animosity, New York City still managed to work out a more equitable land-acquisition and compensation program; this involved diplomacy and cash instead of the hard-handed eminent domain method used before.

The big take home message from this entire situation is that preservation of ecosystems services can be much more economical than creating a man-made solution for something nature is already doing every day. Another key message is that it is very complicated to understand the factors involved in implementing such a widespread plan, but with the right understanding, information, and push it can be done. The next big question is, where can similar plans that involve payment for and preservation of ecosystem services be put into place? The chart below is a great framework for the location specific consideration and understanding needed to implement similar plants.

Figure 3: Diagram of different factors, stakeholders, and steps to analyze when implementing a watershed management/preservation policy or program (7).


(1) Watershed Services. United States Department of Agriculture, 29 May 2009. Web. 12 June 2013. <>.
(2) Pagiola, Stefano, et al. "Paying for the environmental services of silvopastoral practices in Nicaragua." Ecological Economics 64.2 (2007): 374-385.
(3) N.d. Photograph. Trinity Basin Conservation Foundation, 2011. Web. 12 June 2013. <>.
(4) United States Geological Survey, 2010. Web. 12 June 2013. <>.
(5) Forest Trends, 10 Feb. 2006. Web. 12 June 2013. <>.
(6) Safe Drinking Water Act (SDWA). United States Environmental Proteciton Agency, June 2004. Web. 12 June 2013. <>.
(7) Porras, Ina T., Maryanne Grieg-Gran, and Nanete Neves. All That Glitters: A Review of Payments for Watershed Services in Developing Countries. London: IIED, 2008. Print.
(8) Postel, Sandra L., and Barton H. Thompson. "Watershed protection: Capturing the benefits of nature's water supply services." Natural Resources Forum. Vol. 29. No. 2. Blackwell Publishing, Ltd., 2005.

(9) Pattanayak, Subhrendu K. "Valuing watershed services: concepts and empirics from southeast Asia." Agriculture, Ecosystems & Environment 104.1 (2004): 171-184.

No comments:

Post a Comment