Water & Infrastructure Group Meeting  

April 28, 2022   7:00pm

Speaker: Melissa Von Mayrhauser,
PhD. Candidate at UC Berkeley

Changing River Flows and Novel Ecosystems in the Los Angeles and Santa Clara River

Could water conservation mandateshave unintended consequences
for Southern California rivers? 

Changing River Flows and Novel Ecosystems
in the Los Angeles and Santa Clara River

The Los Angeles and Santa Clara Rivers have historically flowed only part of the year. But today they flow at all times of the year, largely due to treated wastewater discharge.

These changes, paired with extensive development, have led to the growth of invasive species such as giant cane. At the same time, year-round flows also provide key habitat for birds, such as yellow warblers and great blue herons, as well as some threatened and endangered species, including tri-colored blackbirds.

Now these flows will be reduced as Los Angeles and other cities look to build drought resilience by treating and reusing wastewater, rather than discharging it into rivers.

With mandates calling for reduced discharges as early as 2022, some parts of these rivers will likely dry seasonally.

Alongside collaborators at UC Berkeley and the Southern California Coastal Water Research Project (SCCWRP), Melissa von Mayrhauser is researching to what extent changes in flows might cause changes in aquatic and riparian vegetation, as well as bug and bird communities along these waterways.

Using a combination of satellite analyses and collecting specimens, and pairing this ecological analysis with a study about how reduced flows might change people’s perceptions and recreational uses of these rivers, this study will have implications for flow-based river restoration strategies, and will inform decision-making around using wastewater effluent as a tool to restore urban river ecosystem health.

In her presentation, she will discuss the historical and current political and ecological context, share progress on her research, and engage with audience members about their thoughts on the future of Southern California rivers.

Join Zoom Meeting

Meeting ID: 883 5815 2110
Passcode: 541509
One tap mobile +16699006833,,88358152110#,,,,*541509# US (San Jose)

Melissa von Mayrhauser is a freshwater ecology PhD student at UC Berkeley. She researches the ecological and social dimensions of restoration in urban rivers with a focus on Southern California. Central themes of her research include intermittent stream ecology, urban watershed management, and community-based biodiversity data collection.

Previously, as the Watershed Programs Manager at the NGO Los Angeles Waterkeeper, she tied together scientific fieldwork, policy change, and community participation to improve the health of the LA River and surrounding communities. She has an MSc in Water Science, Policy, and Management from the University of Oxford. She enjoys making iNaturalist observations on meandering walks.