Valuing the Benefits of Ecosystem Services Generated by the Reed Canyon Restoration Project: 1999-2009
The Reed College Canyon is a 28-acre natural area located on the 116-acre Reed College campus in Southeast Portland, Oregon. An extensive restoration project was initiated in 1999 to remove a large concrete structure and invasive plant species. Access to the Reed Lake for anadromous species was improved when a fish ladder was built; an extensive planting program using native plant species has helped restore the canyon to a more natural state. To date, almost $500,000 of private contributions and government grants have been invested in the restoration project.
This report, a collaborative effort by students in the fall 2009 Natural Resource Economics class, evaluates and values the change in ecosystem services from restorating the Reed College Canyon. Ecosystem goods and services include: water quantity and quality, air quality, wildlife habitat and recreation. Values were generated using the benefit transfer technique, a well-established methodology that allows researchers to generate proxy values for environmental goods and services at a specific place they are interested in, called the study site, by transferring values from other valuation studies conducted at other sites, called the policy site--in our case the Reed College Canyon.
We conducted an extensive literature review to identify studies that would allow us to value the change in each ecosystem good or service generated by the restoration effort. Relevant research and estimates were identified for wildlife habitat and air quality, but no published studies were found linking changes in the conditions of riparian areas and the associated impacts on recreation. Our analysis found that the effects of the restoration project on water quality and quantity are likely swamped by larger hydrologic patterns of the Crystal Springs System, so the value attributed to that ecosystem service is inconclusive.
Our estimate of the value of wildlife habitat improvement due to the restoration project is approximately $15 million. This estimate is a result of increased property values within ¼ mile of the Reed Canyon. Air quality measurements for NO2, particulates and CO2, based on primary research, are all lower in proximity to the Reed Canyon. Studies relating pollution and health effects were used to value the reduction in NO2, particulates, and CO2 because of vegetation in the Reed Canyon. Recreation likely increased as a result of the restoration project, but no data are available to document this change. A study measuring the value of permanently preserving an area, such as the Reed Canyon, for recreation and related benefits was used to place a value on the existence of the canyon (both use and nonuse values).
It would be inappropriate to simply add up our estimates to arrive at an aggregate dollar value for the restoration project or for the Reed Canyon. Some ecosystem goods and services overlap-for example, the extensive planting effort has probably affected each ecosystem good or service. Additionally, some values cannot be estimated because the relevant literature does not exist; for example, there is limited literature examining the value of species listed under the Endangered Species Act (Coho, Bald Eagles, steelhead trout) that use the Reed College Canyon. Present calculations are minimum valuations of ecosystem services that do not indicate comprehensive restoration worth.