70,000 planted at Oro Loma


Last year when Habitat Restoration Director, Donna Ball, proposed a project for Save The Bay’s restoration team to plant 70,000 native plants on an experimental horizontal levee I thought, this sounds near impossible….let’s do it! And with that, we hit the ground running, in preparation for what would be the biggest and most ambitious project Save The Bay’s restoration team had ever attempted.

Over the past 16 years Save The Bay has engaged thousands of volunteers to plant roughly 30-50,000 plants each winter. This year the Horizontal Levee Project at the Oro Loma Sanitary District, combined with our work at various sites around the Bay, will top 100,000 native plants being installed in our restoration projects. But how could we possibly do it? That was the task I was given. To work with our nursery manager, Jessie Olson, to collect, propagate, and outplant tens of thousands of plants.

Getting creative with rhizomes

With our nurseries already at capacity for our other restoration projects, we needed to get creative in order to be able to propagate the 70,000 plants. That’s where ecologist Peter Baye’s help comes in. With his extensive knowledge of the Bay’s ecology, native flora, and restoration practices, he advised Save The Bay’s restoration team on how and where to collect certain plant species and how to propagate the plants using rhizomal divisions.

The idea was fairly simple. Instead of growing individual species in separate containers, we would grow the rhizomatous species in raised beds that we would later dig up, divide, and transplant on site. What exactly is a rhizome? If you missed my previous blog, a rhizome if a modified stem that grows horizontally underground and produces new shoots above ground. It’s almost like they clone themselves.

4 million seeds and counting

With the plan set, we started collection in the field. We had ambitious goals to collect thousands of rhizomes and over 4 million seeds. With collection permits from various parks and reserves, the restoration staff dug up rhizomes and collected ripe seed starting Fall 2014.

During this time, we also went to work building a dozen raised beds on site at Oro Loma. After collecting in the field, the rhizomes were then planted into the raised beds. Our all star volunteers and restoration fellows were of crucial help throughout the collection and transplanting process. Once the beds were planted, all there was left to do was wait for them to do their thing. And they did. Six months later, the small rhizome fragments spread out and produced new shoots, densely filling the raised beds.

Ambitious planting goals

With half of the project accomplished, we were then faced with a bigger challenge, outplanting 70,000 plants… This is where I had to develop new strategies. To aid the restoration staff, I recruited a volunteer planting crew. Lucky for us we had three amazing people join our team for three months, Kelly Franson, Paula Pieriea, and Kelly Hood. We trained them on our restoration techniques and set off with the Horizontal Levee Project Kickoff event on November 14, 2015.

With 2,300 plants installed on the first day, we were off to a good start.

Each day thereafter our staff, all-star volunteers, and planting crew worked rain or shine harvesting rhizome divisions from our raised beds and planting them in a specific planting plan outlined with color coded flags on site. Several public volunteer programs helped our efforts as well as workdays with other restoration teams from around the Bay, including The Presidio Trust and Acterra. Two and a half months later we planted the final plant on the horizontal levee.

What seemed nearly impossible was complete. From the field to the raised beds, to the horizontal levee these plants have had an amazing journey, and so has Save The Bay’s restoration team. We are all proud to have been a part of this innovative project that takes a multi-pronged approach to filter our wastewater and prepare for rising seas, all while providing crucial native habitat at the Bay’s edge.

Learn more about the Oro Loma Horizontal Levee Project:

Project overview

The science of wetlands and wastewater

Experimental habitat for a better Bay

Experimental Living Levee Could Battle Rising Bay Tides — NBC Bay Area

The science of wetlands and wastewater


At Oro Loma Sanitary District, Save The Bay is playing an active role in a restoration project that could provide a blueprint for climate change adaptation around the bay. Though it has a simple appearance, the horizontal levee is actually a complex system that can protect traditional levees from storm surges, provide habitat for vulnerable Bay Area flora and fauna, and reclaim the water that flows out of wastewater treatment plants. Traditionally, this nitrogen containing water would be pumped into the middle of the Bay and forgotten about, but the increased presence of algae in the Bay serves as a helpful reminder that we are failing to protect our ecological neighbors.

Rethinking wastewater

Certain chemicals that come out of our wastewater treatment plants can cause algal blooms at high enough concentrations, but we shouldn’t necessarily regard them as “contaminants.” These chemicals, various forms of nitrogen and phosphorus that are given the label “nutrients”, are the same ones that we use to fertilize our plants and crops. In the wrong place, they can throw off the ecological balance (read: algal blooms). However, if we divert these chemicals to terrestrial plant roots and microorganisms in the subsurface, we can provide plants with nutrients that are needed for growth while preventing those chemicals from making their way into aquatic environments where they can be troublesome. This process can kill two birds with one stone (metaphorically of course, as the levee provides important habitat for birds!)

This is the root of my interest in the restored habitat at Oro Loma. As a part of my research at UC Berkeley, I will monitor the horizontal levee to track chemicals in wastewater as they enter and leave the restored habitat. This is a large-scale experiment, testing to see if a restored habitat can thrive on the outflow from a wastewater treatment plant, as well as whether or not the habitat reduces the concentration of potentially dangerous chemicals that flow through it. By measuring the levels of these chemicals in the water, soil, and plants that the slope is made of, we will be able to understand better the chemical transformations that occur in the horizontal levee, many of which are performed by microorganisms.

Filtering chemicals

But I don’t plan to focus on only nitrogen and phosphorus. Many other chemicals that we put in or on our bodies, such as pharmaceuticals, antimicrobials, food additives and chemicals in personal care products, are collected in wastewater and pass through treatment plants largely unaffected. These chemicals form a group of chemicals known as “trace organic contaminants” many of which may pose threats to living things. The hope is that they will get filtered out of water that flows through the horizontal levee. If everything goes as planned, the slope should act as a sponge, absorbing the chemicals into “sticky” components of the slope, such as dead leaves, roots, and residues from microorganisms. Once absorbed, it is possible that microorganisms will naturally break these chemicals down into less harmful byproducts. Depending on the chemical, this process could be very effective or may do little to help, but these processes are not fully understood and require further study.

This is a fairly new concept and we can’t be certain of how effective it will be, but that is why we are testing it. Before we line the Bay with horizontal levees, we need to make sure we understand how they work. This is a promising new way to pair enhanced wastewater treatment with habitat restoration, and I am thrilled by the role I get to play in studying it!

– Aidan Cecchetti

IMG_1988_cAidan Cecchetti is a graduate student at UC Berkeley where he is working on his PhD in Environmental Engineering. Originally from northeastern United States, Aidan grew up wandering the forests of New Hampshire. After finishing his undergraduate degree at the University of New Hampshire in 2013, Aidan made his way to the Bay Area for graduate school and has been here ever since. In his free time, Aidan enjoys exploring the pockets of nature around the Bay Area, entertaining his cat or playing piano.


Planting begins at Oro Loma

Oro Loma
Volunteers planted 3,200 native seedlings at the Oro Loma Horizontal Levee Project. Save The Bay will plant 70,000 seedlings at this site over the coming months.

Last weekend, over fifty volunteers gathered at the Oro Loma Sanitary District treatment plant in San Lorenzo to kick off an ambitious burst of planting activity in a soon-to-be restored wetland.  Participants included a contingent of local college students, parents and their teenage children, and a few veteran helpers.  Equipped with trowels and picks, attendees placed 3,200 plants into a plot of soil next to the sewage treatment plant.

Though the plants were all put in the ground in about an hour, an enormous amount of planning went into how they were selected and configured.  Save The Bay’s habitat restoration team has been working for over a year to cultivate several palettes of wetland plants that will be planted next to each other.  They will become part of a scientific experiment exploring what combination of plants and soils can best filter excess nutrients from the treated wastewater that will be pumped in from the adjacent sewage plant.

A new kind of levee

This is exciting, because if this pilot project is successful, it could be replicated elsewhere as a means of naturally improving water quality, providing needed habitat for sensitive species, and forming a more durable barrier to flooding from storms and sea level rise.  This horizontal levee is an alternative to steep earthen or rock walls that traditionally separate the Bay from vulnerable land — this marsh will gently slope upwards, enabling it to better adapt to rising tides.

After the planting was completed, participants joined the public open house being hosted by the Oro Loma Sanitary District.  Horizontal levee project scientists and treatment plant workers were on hand to give tours, and Save The Bay staff answered questions about their work.  Also present were local elected officials, representatives of the Castro Valley Sanitary District, which co-owns the treatment plant, as well as UC Berkeley researchers who will analyze the filtering capacity of the wetland once it is operational.

Over the next two months, our goal is to put in 70,000 plants at this site.  If this project sounds interesting and you’d like to pitch in, you’re in luck!  Save The Bay will be hosting 3 more volunteer planting workdays at Oro Loma, on November 21, December 5, and December 12.  Click here to volunteer!

“Surviving the Storm” by Saving the Bay

Surviving the Storm
The Bay Area Council’s report “Surviving the Storm” estimates that a superstorm in the Bay Area would cause $10.4 billion of damage. Restoring the Bay’s wetlands will help protect our communities from flooding.

Four years into a record-breaking drought, few of us in the Bay Area are worrying about the harm that might happen if we get too much rain all at once, but a newly published report says that we should be.

Last Monday, the business-backed Bay Area Council released “Surviving the Storm,” a study of the economic damage that would occur in the event of the kind of powerful superstorm the Bay Area is expected to suffer once every 150 years, and perhaps more frequently as our region’s climate grows more volatile and we experience increasingly extreme weather due to the effects of climate change.

The study estimates that such a storm, dropping 12 inches of rain in a week, would cause $10.4 billion of damage region-wide, almost as much as the 1989 Loma Prieta earthquake. Santa Clara County would suffer the greatest losses – more than $6 billion – while San Mateo and Marin counties would each lose more than $1 billion, and Alameda and Contra Costa counties would each lose about $750 million.

Strikingly, these enormous figures actually understate the potential damage such a storm would cause, as the study’s estimates do not include the costs of repairing the region’s airports and highways, do not account for the significant possibility of levee failure in Sacramento-San Joaquin River Delta, and do not factor in the additional impacts attributable to anticipated sea-level rise of as much as two feet by 2050.

The good news is that this huge risk to our region’s economy is largely preventable, and that accelerating the large scale restoration of San Francisco Bay’s wetlands is a big part of the solution.

One of the report’s key recommendations is to, “Support funding for the San Francisco Bay Restoration Authority to restore wetlands and provide associated flood protection,” and the report further features the use of “wetlands and other natural systems to provide reliable and cost-effective flood protection while providing wildlife habitat and other ecosystem benefits.” Such flood protection mechanisms include the use of “horizontal levees” that integrate traditional grey infrastructure with green transition zones so as to enhance flood resiliency, increase habitat diversity, and provide public access to the Bay.

The report’s inclusion of these elements highlights the growing consensus regarding the crucial role that wetlands restoration should play in helping address and adapt to the effects of climate change. Save The Bay Executive Director, David Lewis, commented on the report: “Restoring the Bay will help protect our communities from flooding and promote our region’s economy, all while enhancing water quality and wildlife habitat. This report shows why wetland restoration projects have overwhelming public support.”

Save The Bay is joining the Bay Area Council and other key stakeholders to raise awareness among businesses, elected officials, and community leaders about the potentially devastating consequences of a superstorm driven flood, and the critical role of accelerated, large scale wetlands restoration in protecting our region.