Reports & Key Findings

Public-Private Partnership and Large-scale Use of Green Infrastructure in the Great Lakes Basin

This report presents the findings of an initiative to expand the use of green stormwater infrastructure in the Great Lakes Basin through the use of private financing and/or private delivery. Presented here-in are assessments of the market size, key drivers of green stormwater infrastructure, benefits of private delivery/finance, and relevance of stormwater utilities.

Key Findings:

Market Size in the Great Lakes Basin

Stormwater utilities and their associated fees are an attractive means of repaying private investments. Ohio, Minnesota, Wisconsin, Illinois, and Indiana, collectively, have a large and growing number of stormwater utilities that generate a dedicated revenue stream, a portion of which could be used to support private financing/delivery of large-scale green infrastructure. We estimate that the potential market size for private investment in green infrastructure exceeds a billion dollars in these five states.

Market Drivers

Market drivers for private delivery and investment in large-scale green infrastructure are enhanced by community leadership, cost effectiveness, efficient and cheaper project delivery, performance based risk transfer, strong regulatory drivers, availability of dedicated stormwater funding, and P3-enabling legislations.

Relevance of Stormwater Utilities

Lack of a dedicated funding source limits the ability to attract private and public investment. New York, Pennsylvania, and Michigan have no or very few stormwater utilities in place limiting their ability to repay stormwater investments.

Status of P3 Legislations

Although the absence of a stormwater P3 legislation is not entirely prohibitive, its presence greatly facilitates the enactment of a P3. Only two Great Lakes states, Michigan and Indiana, have enacted P3 legislations for non-transportation projects. In other states, Home Rule authorities may be used to bypass the lack of P3 legislations.

Market-based Alternative Delivery and Finance Options to Implement Large-scale Green Infrastructure: Recommendations to the Milwaukee Metropolitan Sewerage District

After analyzing a variety of P3 options, project team recommends considering the use of either a CBP3 or an EIB for MMSD to meet its 2035 Green Stormwater Infrastructure vision. To enact a CBP3, MMSD doesn’t need private finance, and it can utilize its excellent credit rating to access best-fit public financing/funding strategies via various low-cost tax exempt and/or taxable capital sources, such as State Revolving Fund (SRF) and/or Water Infrastructure Finance and Innovation Act (WIFIA) loans, municipal bonds, existing property taxes and other general funds. Alternatively, MMSD can use an EIB that allows access to new capital and leverage a high degree of flexibility to scale innovations via a pay-for-performance framework.

Key benefits of a CBP3 to MMSD
  • MMSD and communities retain ownership, governance and decision authority.
  • MMSD and communities retain program savings.
  • Accelerated delivery of a large number of projects.
  • Private partner compensated on performance and achievement of aligned goals and objectives.
  • Private partner retains risk for project delivery, maintenance, etc.
  • Partner is responsible for the achievement of goals through the management of design, build, operation and maintenance processes.
  • Workforce development, economic development, and other socially driven goals can be a CBP3 contract requirement.
Key benefits of an EIB to MMSD
  • Ease of execution and access to new sources of impact capital, which can accelerate funding for innovative uses.
  • Lack of a long-term encumbrance of an asset.
  • High degree of flexibility to scale innovations and transfer risks from pilot projects.
  • Meet the borrowers’ environmental and social objectives.
  • Possibility of engaging multiple payors who benefit from green infrastructure projects (e.g., housing authority, economic development, public health, etc).
  • Ability to use a variety of preferred delivery methods with the public borrower(s) retaining or transferring construction and maintenance risks to the private partner.

Market-based Alternative Delivery and Finance Options to Implement Large-scale Green Infrastructure: Recommendations to the Northeast Ohio Regional Sewer District

A set of public-private partnership options were analyzed for NEORSD that included a CBP3, an EIB, and stormwater credit trading. Of these, stormwater credit trading emerged as the preferred partnership model for NEORSD. To have a successful credit trading program, NEORSD will need to to enact a new low-impact development ordinance, and an in-lieu option as well as a purchase guarantee of credits.

Key Benefits of a Stormwater Trading Framework to NEORSD:

Extension of current program

It is an extension of NEORSD’s current impervious cover fee program.

Retain Ownership and Governance

NEORSD and communities retain ownership, governance and decision authority that guides the framework.

Leverage optimal use

It allows the ability to leverage the uneven rate of economic recovery by prioritizing green infrastructure in areas of lower growth.


Costs of such a program are largely borne by developers.

Access to private properties

It is a flexible framework that will allow access to private properties in the service area.

Accelerated Delivery

Accelerated delivery of a large number of projects instead of delay due to lack of upfront capital.

Local Workforce Development

Workforce development, economic development, and other socially driven goals can be achieved if the framework is designed appropriately.