Essential water policy reforms for managing drought in California

Check out the latest report from PPIC’s Water Policy Center, which recommends water policy reforms for avoiding negative social, economic, and environmental consequences from drought and a changing climate. Key reforms include:

  • Plan ahead. Stronger drought planning is critically important for urban water management, groundwater sustainability, safe drinking water in rural communities, and freshwater ecosystems.
  • Upgrade the water grid. California needs a comprehensive program to address above- and below-ground storage, conveyance, and operational challenges by mid-century, including repairing facilities that are broken, expanding conveyance and storage capacity, and modernizing and integrating operations.
  • Update water allocation rules. California should comprehensively update its water allocation governance. The goals should be to find equitable and efficient ways to allocate limited supplies among competing demands during dry times while promoting efforts to capture and store water during wet times.
  • Find the money. Reliable funding is crucial for adapting to climate change. New sources are needed to pay for necessary water-management investments and to fill funding gaps in the state’s water system.

Welcome to Rachael Ryan!

Rachael Ryan is a new grad student in the #BerkeleyFreshwater group, and will be co-advised by Stephanie and Ted. Rachael plans to explore the influence of climatic variation and habitat mosaics on distribution, abundance, and diversity of coho salmon in the Lagunitas Watershed, in west Marin. Stay tuned for updates!

August 2018 updates

May 2018 updates

  • May was travel month! Albert participated in a Powell Center workshop on the Budyko framework–this interdisciplinary working group is ongoing and will present in next AGU Fall Meeting on the cumulative effects of dams on flow regime alteration.
  • The Berkeley Freshwater Ecology labs also attended the Society for Freshwater Science Annual Meeting in Detroit, MI. It was a great combination of science & fun.
  • Meanwhile, visiting researcher Maria went back to Spain after a productive stay analyzing arthropod metacommunity data from intermittent streams.
  • Last but not least, the lab renovations were completed!

 

New paper in Global Change Biology

Interested in how hydropower dams affect flow regimes and downstream biodiversity? Here we sought to understand the ecological effects of flow management for hydropower (hydropeaking). Collaborating with Darold Batzer’s lab at UGA, we found that hydropeaking can spatially synchronize trait fluctuations and simplify the functional structure of downstream invertebrate communities. Still interested? Then read more below!

Abstract

Novel flow regimes resulting from dam operations and overallocation of freshwater resources are an emerging consequence of global change. Yet, anticipating how freshwater biodiversity will respond to surging flow regime alteration requires overcoming two challenges in environmental flow science: shifting from local to riverscape‐level understanding of biodiversity dynamics, and from static to time‐varying characterizations of the flow regime. Here, we used time‐series methods (wavelets and multivariate autoregressive models) to quantify flow‐regime alteration and to link time‐varying flow regimes to the dynamics of multiple local communities potentially connected by dispersal (i.e., a metacommunity). We studied the Chattahoochee River below Buford dam (Georgia, U.S.A.), and asked how flow regime alteration by a large hydropower dam may control the long‐term functional trajectory of the downstream invertebrate metacommunity. We found that seasonal variation in hydropeaking synchronized temporal fluctuations in trait abundance among the flow‐altered sites. Three biological trait states describing adaptation to fast flows benefitted from flow management for hydropower, but did not compensate for declines in 16 “loser” traits. Accordingly, metacommunity‐wide functional diversity responded negatively to hydropeaking intensity, and stochastic simulations showed that the risk of functional diversity collapse within the next 4 years would decrease by 17% if hydropeaking was ameliorated, or by 9% if it was applied every other season. Finally, an analysis of 97 reference and 23 dam‐affected river sites across the U.S. Southeast suggested that flow variation at extraneous, human‐relevant scales (12‐hr, 24‐hr, 1‐week) is relatively common in rivers affected by hydropower dams. This study advances the notion that novel flow regimes are widespread, and simplify the functional structure of riverine communities by filtering out taxa with nonadaptive traits and by spatially synchronizing their dynamics. This is relevant in the light of ongoing and future hydrologic alteration due to climate non‐stationarity and the new wave of dams planned globally.

Ruhi, A., Dong, X., McDaniel, C.H., Batzer, D.P. and Sabo, J.L., 2018. Detrimental effects of a novel flow regime on the functional trajectory of an aquatic invertebrate metacommunity. Global Change Biology.