Ecosystem Reducing Cost Uncertainty
in Ecosystem Restoration

Estimating the costs of aquatic ecosystem restoration is challenging. Many variables and factors associated with restoration projects, such as project design, equipment mobilization, land acquisition, and construction, make it difficult for accurate cost projections. Many times restoration managers are faced with significant differences between projected costs and actual expenditures. The end result is often the request for additional funds.

Most recently Battelle was engaged by the U. S. Army Corps of Engineers (USACE) to explore the differences between estimated and actual costs of a variety of habitat restoration projects. Battelle’s task was to identify ways to reduce the cost uncertainty associated with project costs. This expands on previous Battelle research, conducted as part of the Evaluation of Environmental Investments Research Program, by comparing estimated costs and actual project expenditures.

Management Measures

Battelle developed an analytical approach that included both quantitative and qualitative survey data. Data were collected from a representative group of 47 restoration projects from across the country. To identify the factors most directly linked to cost uncertainty, estimated and actual expenditures were considered at an aggregate level. For more accurate source identification, Battelle categorized the data according to five key management measures: water control structures, revegetation/planting, integrated ecosystem restoration, channel improvements, and dikes and levees.

Battelle’s preliminary quantitative assessment of data revealed several important results:

  • For 30 percent of the sample, actual expenditures exceeded projected costs by $100,000 or more than 20 percent of the original estimates.
  • Project overruns varied from less than $100,000 to more than $2 million.
  • Cost disparities were generally not linked to systematic errors in estimating the per unit cost of labor and materials.
  • Cost uncertainties were more prevalent in large, integrated restoration projects.

Notably, Battelle found that the frequency of significant differences between projected and actual cost decreased over time. Experience gained in implementing restoration projects sharpens the ability of planners to accurately estimate costs. Battelle confirmed these observations during discussions with project managers. The interviews also corroborated general findings with regard to cost uncertainty. Battelle’s results suggest that differences between estimated and actual costs are most directly linked to the following:
  1. Incomplete on-site surveys;
  2. Insufficiently detailed planning;
  3. Lack of project experience;
  4. Difficulties in project scheduling;
  5. Problems in land acquisition; and
  6. Unanticipated weather.

Some factors, such as inadequate surveys, insufficiently detailed planning, and unrealistic scheduling can be addressed through implementation of specific program policies, but others represent uncontrollable factors inherent to habitat restoration.

Looking forward, Battelle’s continued restoration assessment will assist in reducing costly overruns and direct funds towards long-term monitoring programs and other restoration projects.

For more information on Battelle’s restoration programs, please contact Ron Thom at (360) 681-3657 or via e-mail at ron.thom@pnl.gov.

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