Bridging the Divide: Connecting Stormwater and Floodplain Management in Oregon

Introduction

Our water resource management challenges are significant and often complex. We are trying to manage the flooding effects of more and more intense storms, the adverse effect of past and present urbanization on watershed processes, and loss of habitat that affects native migratory fish, among other things. There is a growing recognition that we cannot meet today’s water resource challenges by working in silos – with wastewater, stormwater, drinking water, groundwater, and flood waters addressed separately. Communities are now looking for the policy and planning tools to meet these challenges efficiently and to help them become more resilient. They are looking for ways to address multi-faceted problems with integrated solutions.

In Oregon right now, the intersection of stormwater and floodplain management is particularly relevant. Floodplains and stormwater may be distinct legal arenas, but they are hydrologically connected and the state and federal regulatory programs that govern them are changing.

• Stormwater: The municipal separate storm sewer system (MS4) permits require action to address the water quality impacts of stormwater. Oregon Department of Environmental Quality’s (DEQ) MS4 permit program continues to evolve, increasing a community’s obligation around monitoring and management, and in some cases, the effects on watershed hydrology.

• Floodplains: The 2016 Biological Opinion, issued by the National Marine Fisheries Service (NMFS BiOp), for FEMA’s National Flood Insurance Program is driving planners and floodplain managers to think more about addressing the water quality, hydromodification, and habitat impacts of stormwater as a means of protecting endangered species in floodplains.

Over the past year, Willamette Partnership and Oregon Association of Clean Water Agencies (the Project Team) have been collaborating to better understand the intersection between stormwater and floodplain management, seeking to bridge the divide between these silos of water management and helping communities realize the benefits of an integrated approach – more efficient, effective, ecologically and economically resilient approaches to surface water management.

This effort, funded by the Oregon Community Foundation, included interviews and a collaborative workshop with stormwater managers, floodplain managers, city planners, and other water resource managers and decision makers from 10 communities across Oregon to:

1. Build a common understanding of regulatory obligations related to stormwater permits and the NMFS BiOp, focusing specifically on where they can overlap;

2. Inform integrated approaches to policy and planning that meet stormwater and floodplain requirements.

This report provides i) a brief overview of the way that regulatory drivers and local programs affect stormwater and floodplain management in Oregon, ii) a summary of the challenges to and opportunities for integrated strategies identified through interviews and the workshop, and iii) recommendations for moving forward together. The report is intended to inform discussion around the connections between stormwater and floodplain management, and the development of efficient and effective approaches that water resource managers can take to meet the surface water challenges that communities face.

Read “Bridging the Divide: Connecting Stormwater and Floodplain Management in Oregon”