New Guidelines Will Help Make Water Infrastructure Projects More Resilient

The Water Resources Reform and Development Act of 2014 (WRRDA) made several changes to the federal statute governing the Clean Water State Revolving Fund (CWSRF), a funding program that has provided a total of more than $105 billion for a variety of wastewater, stormwater, and other water quality improvement projects. Many of these changes, which I have previously written about, will better prepare communities for severe storms, drought, flooding, and a variety of other extreme weather challenges. One of the most important revisions, which went into effect this past October, requires all CWSRF applicants to assess the economic and environmental costs and benefits of incorporating a range of water efficiency, stormwater capture, water reuse, and energy efficiency measures into their proposed projects. These types of solutions provide multiple benefits, such as eliminating or delaying the need for capital projects, lowering operating costs, protecting environmental resources, and increasing resilience to climate risks.

In January 2015, the U.S. Environmental Protection Agency (EPA), which is the federal agency that jointly manages the CWSRF along with the states, released its final guidance for state SRF programs and EPA regions on how to implement the WRRDA changes. Unfortunately, this interpretive guidance did not include specific criteria or guidelines for how state CWSRF managers and project applicants should go about evaluating and incorporating cost-effective conservation, stormwater capture, and reuse practices. To address this gap, we contracted with Stratus Consulting (now a part of Abt Associates) to develop guidelines to help state CWSRF managers and project applicants meet these new requirements. Following this framework will result in more CWSRF projects incorporating innovative and forward-looking solutions that can lower water demand, improve the reliability of existing supplies, decrease energy demands, and reduce polluted runoff instead of solely relying on oftentimes outdated and costly concrete and steel infrastructure. We urge states to adopt these guidelines to help project applicants conduct cost and effectiveness analyses that maximize the potential for these sustainable solutions.

The Stratus guidelines (available for download at outline a seven step economic framework, which is summarized below, for project applicants to follow to evaluate alternatives to their proposed project:

  • Step 1. Define the Project Objective

In this step, project applicants determine what problem the proposed project is intended to resolve. Articulating the primary objective of a project allows applicants to identify alternative project options, including green infrastructure, reuse, and water- and energy-efficiency options, to compare how well those options might solve the identified problem.

Example: Manage stormwater runoff from 2,000 impervious acres to reduce annual sewer overflows by 50 percent in the Town Creek watershed.

  • Step 2. Establish the Baseline

A baseline scenario allows for the measurement and comparison of project alternatives. It also helps to identify avoided costs and/or foregone benefits associated with project alternatives. For most project applicants, the baseline scenario will likely include an already-planned project or a traditional "gray infrastructure" project approach.

Example: Construct tunnels to capture and treat stormwater though a combined sewer system.

  • Step 3. Identify Alternative Project Options

A project applicant should now identify and conduct an initial screen of alternatives that meet the project objective, including options that incorporate efficiency, reuse, and recapture. This step includes determining whether there are efficiency, recapture, and reuse measures that either fully or partially meet the project's objectives in addition to examining whether alternative materials or equipment can be used to maximize energy and water efficiency and/or stormwater capture when the project is implemented.


Alternative A - Evaluate options for capturing 30-60 percent of runoff from impervious area using green infrastructure; downsize tunnel project accordingly.

Alternative B - Evaluate options for capturing 30-60 percent of runoff from impervious area using green infrastructure; implement satellite treatment facilities to reduce energy use associated with pumping; downsize (or eliminate) tunnel project accordingly.

  • Step 4. Identify and Quantify Project Costs and Key Benefits

The next step involves inventorying all likely costs and benefits associated with each of the project alternatives identified in Step 3. A full benefit-cost analysis is not necessary; however, it is important to identify the full suite of benefits associated with each alternative so that they can be used to inform the decision-making process in at least a qualitative way.

Examples of project costs: engineering and design; environmental mitigation; right-of-way acquisition; construction; O&M; replacement costs; salvage value; temporary and permanent public impacts (e.g., traffic, noise, dust); public relations

Examples of project benefits: physical quantity associated with key project benefits (e.g., reduction in overflows, energy savings); avoided costs if project alternative is implemented (e.g., water efficiency measures that result in avoided costs of securing additional water supplies); other financial, environmental, and/or social benefits

  • Step 5. Develop Lifecycle Analysis

The costs and benefits of CWSRF projects generally occur over time. For example, a project may have initial capital costs in the first few years of construction and then annual O&M costs through the remaining project lifetime. Adjusting future costs and benefits to their "present value" allows for a comparison of project costs per unit of benefit for each of the project alternatives (e.g., $/gallon of stormwater captured, $/unit of water savings).

  • Step 6. Incorporate Non-Monetary Benefits and Costs

It is not always feasible to incorporate all costs or benefits in a quantitative or monetary way. However, when evaluating project alternatives, it is important to describe these benefits and costs in a meaningful and qualitative manner. One way to achieve this is to use a simple scale to indicate the likely impact on overall project costs or benefits.

Example: A rating scale of -5 to 5, where 1 and 2 are considered low impact, 3 is considered moderate, and a rating of 4 or 5 is high impact. Negative ratings indicate costs, and positive ratings indicate benefits.


Green Infrastructure Alternative

Gray Infrastructure Alternative

Recreational Opportunities



Local Employment



Community Aesthetics/Livability



Energy Savings



Climate Resiliency



Construction/Traffic Disruption



  • Step 7. Summarize and Compare Alternatives, and Determine the "Optimal" Combination of Project Elements

The last step involves synthesizing the information developed in the previous steps and selecting the preferred project alternative. When selecting and developing a final ranking of alternatives, applicants should assess whether the least-cost alternative is also the preferred option or whether a higher-cost alternative that provides important co-benefits should be implemented instead. These types of considerations can be accomplished through a multi-criteria decision analysis or a simple ranking/decision matrix based on costs, benefits, and other factors.

Example: Applicants score each alternative (e.g., on a scale of 1-10) across different cost, benefit, and feasibility categories and then calculate the highest scoring project alternative. Following these steps may result in a project applicant using green infrastructure to reduce peak stormwater flows instead of increasing treatment plant capacity due to the flexibility and numerous co-benefits that green infrastructure can provide (e.g., groundwater recharge, energy savings, increased climate resiliency, improved quality of life).

Alternative 1 (Baseline)

Alternative 2

Alternative 3