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Comprehensive Benefits Evaluation for Nature-Based Solutions

The US Army Corps of Engineers (USACE) Engineering With Nature® Program works to better integrate traditional and nature-based infrastructure approaches by aligning engineering and natural processes for greater benefit.

Summit Success

30 Nov 2022: Measuring What Matters

A multi-sector contribution to practical guidance on formulating, evaluating, and delivering integrated water resources projects. Review the Summit.


Current practice in benefit-cost analysis (BCA) is ‘tuned’ for evaluating the economic (dollar value) of costs and benefits produced by traditional, ‘hard’ infrastructure projects. However, the science and practice of quantifying the economic, environmental, and social benefits and costs of nature-based solutions has grown dramatically in recent years.  If these advancements were implemented, they could provide a more complete assessment of how nature-based solutions can add value as a part of infrastructure systems.

This applied policy research study will evaluate and apply methods for documenting a comprehensive range of economic, environmental, and social benefits that nature-based solutions can provide. Specific consideration will be given to instances in which nature-based solutions are strategically designed to work with, in an integrated fashion, conventional infrastructure approaches.

Delivering infrastructure to sustain our communities, economy and environment calls upon us to innovate, modernize and even revolutionize our approach to infrastructure development. Partnering WITH nature is a vital part of delivering those solutions in the 21st century.

Lt. Gen. Scott Spellmon, Chief of Engineers and Commanding General of the USACE, from his foreword to the recently published Engineering With Nature Atlas Volume 2
A rendering of potential nature-based solution at Franklin Lock and Dam in SAJ. The mangrove islands with boardwalk provide increased habitat for Wood Stork and Snail Kite, educational and recreational opportunities. Learn more about mangrove research.


The USACE EWN® Program has partnered with The Water Institute of the Gulf to analyze past and current benefits evaluation approaches to identify practical options for improving federal practice for evaluating the economic, environmental, and social benefits of natural infrastructure and nature-based solutions. The team is evaluating completed USACE Feasibility Studies / Chief’s Reports to identify opportunities to support comprehensive benefits evaluation for nature-based solutions and infrastructure projects, including factors that may have contributed to prioritizing conventional over natural infrastructure as well as benefits that are not being captured as a part of current practice.

Six Chief’s Reports, from a group of 150 completed USACE Feasibility Studies, have been selected for further analysis within the study.  These reports encompass navigation, coastal storm risk management, flood risk management, and ecosystem restoration missions within USACE.

Selected Historical Planning Studies
  • Jacksonville Harbor (NAV, Sourtheast)
  • Jamaica Bay Reformulation (CSRM, North East)
  • Southwest Coastal (CSRM, Gulf Coast)
  • South Platte River and Tributaries (FRM, Northwest)
  • West Sacramento (FRM, Pacific)
  • South San Francisco Bay Shoreline (FRM, Pacific)

Based on insights gathered in analyzing nature-based alternatives and comprehensive benefits within these six Chief’s Reports, the team will identify opportunities and options for advancing practice for evaluating comprehensive benefits and costs. 

Cormorants gather on a finger of land jutting into the water from the left. The background is a strip of grassland and then an industrial cityscape.
Cormorants, Jamaica Bay Wildlife Refuge. (Photo: Don Riepe) Podcast: EWN for Safe and Livable Cities.


Engineering With Nature emphasizes that current infrastructure project evaluations can be more robust and potentially more protective if costs and benefits of these projects are fully evaluated for the cumulative economic, environmental, and social benefits. EWN does not replace the need for fully engineered concrete infrastructure, but it recognizes that nature-based infrastructure can complement traditional methods for an outcome that is greater than its parts. For example, when a concrete flood wall is designed to include an expansive reef and marsh in front of it, the wall provides flood protection benefits during storms while the reef and marsh system reduce the power of waves, self-adjusts to rising seas, captures carbon, improves water quality, and provides recreational opportunities.

Flooding of Watsonville and agricultural land along the Pajaro River following the March 1995 storm. Learn more about Pajaro River Flood Risk Management.
Horseshoe Bend Island, Atchafalaya River, LA. The river’s current disperses dredged sediment intentionally placed upriver reducing dredging requirements and creating an island with enriched wildlife. (Photo: Great Lakes Dredge and Dock Company) Read more.


This project will provide USACE a baseline to identify how nature-based projects have been evaluated in the past, potential obstacles to advancing practice, and outline how a more comprehensive evaluation of project benefits and costs could provide opportunities to expand and diversify the value provided by infrastructure projects through the inclusion of nature-based solutions.

Engineering With Nature is planning a National Summit on Comprehensive Benefits Evaluation in Washington D.C. during the fall of 2022 to share the results of this study and to invite other federal and state agencies and private sector organizations to share what they are learning about comprehensive benefits evaluation for nature-based solutions.


This study is on-going, additional products and information will be added here.

Evolution of Benefits Evaluation and Prioritization of Water Resources Projects

This report examines: 1) the evolution of USACE’s mission and the related authorities, policies, and practices for using BCA; 2) how challenges in using BCA outside of USACE influence the integration of NBS; and 3) gaps and obstacles within law and policy to further the implementation of NBS projects.

Consideration of Nature-Based Solutions in USACE Planning Studies

Second in a series of reports, this paper outlines the steps and processes taken to select six final case studies for analysis.

Planning and Valuation Methods for Case Study Analysis

The third in a series, this report provides methodological guidance for the retrospective case study analysis and should be of interest to technical readers at USACE, other federal agencies, and interested stakeholders. The report describes recent and relevant decision analysis methods designed to inform decision makers when considering or trading off among multiple objectives when prioritizing water resources projects.


The Corps of Engineers has a proud history of Engineering With Nature and we are honored to work closely with our colleagues across the Corps to collaboratively develop practical tools that support measuring this full range of benefits.

Justin Ehrenwerth, the Water Institute president and CEO