Twenty First Century Water Asset Accounting (PDF)

Green infrastructure, the use of soil, vegetation, and other natural landscape features to manage and treat water, is increasing in popularity as an alternative to traditional grey infrastructure for water management. However, challenges arise to the widespread adoption of green infrastructure practices because of the difficulty in evaluating, accounting for, and valuing the benefits of such practices. Current accounting frameworks do not adequately account for the value of these assets, and the absence of appropriate accounting and evaluation tools may limit the ability of utilities to maintain or expand green approaches. This project developed two potential accounting frameworks to help water utilities assess and account for the ecosystem services provided by green infrastructure. The frameworks were pilot tested at three participating public wastewater and drinking water utilities over a period of five months to assess the benefits and feasibility of implementing national-scale accounting methods for green infrastructure. Several themes on green infrastructure accounting emerged from the pilot tests: the effects of regulatory vs. non-regulatory drivers, the importance of information flow both to the utilities from outside experts and within municipal government, and the need for standardized methods for assessing and accounting for the services provided by green infrastructure. Pilot test participants indicated that with further refinement of the accounting frameworks and the development of standardized guidance for valuing green infrastructure, national-scale implementation of these accounting frameworks is possible. This report discusses the implications of larger-scale adoption and future research needs to facilitate green infrastructure accounting practices.