Onondaga County, New York is a national model for the implementation of a balanced approach to stormwater management. Its Save the Rain program has helped advance more than 175 green infrastructure projects on both public and private property. Lessons learned from the Onondaga County Save the Rain Green Improvement Fund green infrastructure calculator have shaped the business case for all projects within the program, as well as other program critical activities, such as budget forecasting and planning.

By: Matthew Marko, CH2M HILL

Matthew Marko will present the paper “A Business Case Approach for Green Infrastructure Investments—Maximizing Public and Private Investments to Create Progress”, co-authored by CH2M HILL’s Andrew Potts and Brian Marengo, as well as Onondaga County’s Matthew Millea, on Tuesday, September 30 at 1:30 pm, in TS404 during WEFTEC 2014, in New Orleans, Louisiana.

Learn more about CH2M HILL’s WEFTEC 2014 participation and technical sessions.

Green Infrastructure (GI) uses soils, vegetation, and natural processes to mimic nature for sustainable stormwater management and create healthier urban environments. Responsible application of GI is—like any infrastructure, ultimately a financial decision. Evaluating the triple bottom line of GI is important to justify its application; however, social benefits are often difficult to monetize and therefore, a strong business case is needed to sway decision makers to choose green over gray.

New York’s Onondaga County, along with a team of CH2M HILL consultants and the Department of Water Environment Protection, worked together to develop a business case GI calculator, and used it as the foundation to build one of the nation’s first, broadly utilized GI grant programs, known as Save the Rain’s Green Improvement Fund (GIF). The GI calculator enables the County to make a fiscally responsible decision to fund GI projects, while ensuring public benefit through achieving objectives of Clean Water Act compliance obligations.

The calculator works by taking business case metrics, like maintenance, longevity, project geography, and other monetized factors, to identify reasonable compensatory values resulting in grant incentives for multiple GI stormwater control measures, such as as rain gardens, bioretention, underground infiltration systems, green roofs, porous pavements, and even cistern and capture/release systems (which undergo a slightly different valuation process than other GI techniques, due to the competing goals of storing water for reuse yet having capacity available for stormwater capture). The calculator uses four basic principles, including:

  • capture goal,
  • the fixed volume goal based on 1 inch of runoff from impervious areas,
  • GI sized based on the individual drainage area rather than being averaged over a site
  • a solid inventory of GI installation costs compared to gray infrastructure cost alternatives

In addition to the GI calculator, Onondaga County developed a widespread GI framework which incorporates both public and private property, to achieve a 95% system-wide capture goal. Recognizing the benefit of GI on public, as well as private land, the framework incentivizes private property owners to implement GI by funding grants using public-private-partnerships.

The program has been wildly successful and is serving as a national model for stormwater implementation programs. Through March 1, 2014, Onondaga’s Save the Rain GIF grant program has received 140 applications for funding. 59 projects have been completed (27 in 2013). 54 projects are under contract for construction in 2014, and 10 applications are currently being reviewed and finalized.

For those projects completed, 25 million gallons of stormwater runoff are removed from Onondaga County’s combined sewer system, annually. The GIF is one of the most economical facets of the program, achieving that volume capture for approximately $6.5 million. That equates to $0.26/gallon, which is more efficient than the typical public GI project, and far better than the most cost efficient gray alternative.

To learn more about this project, visit us at WEFTEC or drop us a note.

Matthew Marko is a Vice President and Principal Project Manager in CH2M HILL’s Water Market. He has more than 20 years of experience in evaluating complex problems and providing innovation solutions within the design, manufacturing, construction, and operations markets. Matthew currently resides in Syracuse, New York. “I’ve worked with numerous public and private clients throughout my career on innovative project delivery systems, including several large design-build-operate projects,” said Matthew. “In my current role as PM for the first court mandated green infrastructure program, I have really enjoyed working with Joanne Mahoney, Onondaga County Executive, to implement a more sustainable, community friendly approach to abating their CSOs and protecting their water environment.” Matthew graduated from State University of New York at Buffalo with a B.S. in Civil Engineering.