Can functional floodplains enhance post-wildfire resilience of aquatic biota and downstream municipal water supplies?
On this page:
A significant product of the nation’s forests is the provision of clean drinking water, productive fish habitats, and functional freshwater ecosystems. However, post-wildfire watersheds contribute runoff that may affect the quality of water supplies, compromising the ability of riverscapes to provide needed ecosystem services. Protecting, maintaining, and improving the capacity of forested watersheds to be resilient to wildfire will require consideration of both built (e.g., water treatment facilities) and natural infrastructure (e.g., forms of river restoration including floodplains). Human modification of riverscape and floodplain processes have exacerbated post-fire runoff that is detrimental to both the quality of water for municipal uses, as well as functioning ecosystems. Recently, floodplain restoration that re-sets valleys to restore depositional processes has been offered as a potential management action that could confer post-wildfire ecosystem resilience. However, before this method can be effectively applied, evaluations of the conditions in which floodplain reset offers the potential to intercept post-wildfire sediments must be completed. To meet this need, we are evaluating the functional role of modern floodplains (generally modified) and developing modeling scenarios to evaluate the characteristics of watersheds that may make restored floodplains a component of a broader watershed-scale resilience strategy. In this presentation, we will outline our analytical approach. Specifically, we are exploring how restoration of multi-scale floodplain connectivity may increase resilience of municipal watersheds to wildfire. Our goal is to quantify the contribution of floodplain restoration actions to a) reducing post-fire sediment loads and b) creating refuges for aquatic and terrestrial biota during wildfires. Additionally, we are evaluating how spatial and temporal components (e.g. synchronized/desynchronized, centralized/dispersed, connectivity, etc.) of multiple actions interact to amplify benefits.
The views expressed in this abstract are those of the authors and do not necessarily represent the views or policies of the U.S. Environmental Protection Agency or U.S. Forest Service.