Posts Tagged: water

Report: Wastewater recycling essential to resilient water future for LA region

Wastewater recycling in Los Angeles is the focus of a new report released by the UCLA Luskin Center for Innovation and the UC Agriculture and Natural Resources. The report, Making the Most of Landmark Recycled Water Investments in Los Angeles: Technical Advisory Recommendations for the Region, was commissioned by Los Angeles Waterkeeper. The goal of the report is to support ongoing efforts to improve local water security and rely less on expensive, energy-intensive and increasingly unreliable water imports from faraway places, like the Sacramento-San Joaquin Delta and the Colorado River.

Experts involved in developing the report agree that expanding the use of recycled wastewater has emerged as a key, scalable water supply strategy that can offer certainty and reliability in the region in light of our new climate reality.

“Both the Metropolitan Water District of Southern California and the City of LA's Department of Water and Power have made significant investments in wastewater recycling, and they plan to do more,” said Bruce Reznik, executive director of LA Waterkeeper. “But there are a lot of moving parts and some critical decisions to be made in the short term if we're going to make significant progress toward reliable local water supplies.”

“The purpose of this report is to help decisionmakers see the full picture so they can prioritize and develop informed strategies for expanding and integrating the disparate wastewater recycling projects into a more cohesive wastewater system – all while taking community voices and environmental impacts into account,” he added.

Local leaders recognize the region must further invest in equitable, climate-smart, affordable local water strategies. LA County's Water Plan, released in late 2023, calls for 80% of water to come from local sources by 2045 (compared with approximately 40% currently). Four major centralized wastewater recycling projects, including two that are landmark in size and scope, have either broken ground or are in the active planning stages throughout Los Angeles County. Collectively, this regional effort may represent the most important water supply investment in the American West in the last half century.

“In many ways, our region has taken great strides toward embracing wastewater recycling,” said report co-author Edith B. de Guzman, UC Cooperative Extension water equity and adaptation policy specialist. “But we need a clearer pathway for how these projects can be built and possibly integrated into a more cohesive system. This report provides a blueprint for water agencies on the project design, community engagement and governance steps that must be made to ensure progress toward rapidly increasing our local water independence.”

Upwards of $20 billion in investment in wastewater recycling projects is planned for the coming years. But as local water and wastewater agencies make these investments, it's essential that they design systems to both maximize benefits and minimize impacts that could be damaging to people and the environment, all while ensuring water remains affordable. Just as importantly, the report flagged the need to effectively engage the public in key decisions to foster public trust in these emerging water technologies and facilitate coordination between agencies to create a resilient regional water supply system. 

Specific action items identified in the report are organized under eight principal recommendations:

1. Take actionable steps on current key decision points pertaining to major recycling facilities. The report encourages agencies to make several decisions that will impact the design of the overall wastewater recycling systems imminently. These include resolving differences between the City of LA's Hyperion 2035 and Operation NEXT efforts, deciding whether to upgrade existing wastewater recycling infrastructure like the Edward C. Little Water Recycling Facility, and making key pipeline and routing decisions.
2. Conduct a more nuanced regional analysis of system facilities, with an emphasis on evaluating distributed alternatives. While some assessment of a more distributed system has been undertaken, additional analysis is still needed on the issues of energy demand, the cost of distributing water under different alternatives, and impacts on aquatic and marine ecosystems.
3. Identify and establish a structure for collaborative governance that enables agencies to work together to realize a regional advanced wastewater recycling network.
4. Adopt a coordinated monitoring plan to ensure water quality is safeguarded for public and ecological health.
5. Balance the adoption of Indirect Potable Reuse (IPR) and Direct Potable Reuse (DPR) with a near-term focus on IPR to the extent feasible and using DPR to fill in service gaps.
6. Perform robust regional forecast and impact analyses to improve future-proofing of facility and network designs, maximize benefits, minimize harm, and avoid stranded assets.
7. Design and execute a collaborative communication and community engagement strategy that offers a clear narrative, emphasizes the benefits of a secure water supply, meets the needs of water customers, and is delivered by trusted messengers.
8. Coordinate across agencies on strategies to attract project financing while taking household affordability into account.

“This report is by no means the final word,” said co-author Gregory Pierce, research and co-executive director at UCLA Luskin Center for Innovation. “The point of this study is to provide guidance and spur discussion, and we hope and expect to see ongoing research and coordination on all of these issues.”

The report was informed by input from a Technical Advisory Committee of 20 people from fields including academia and think tanks, conservation advocacy, labor, the private sector, and current and former water district leaders not affiliated with the projects that are the focus of the report. This effort also benefited from the feedback and insight of more than 20 public agency representatives, including many from the City of Los Angeles (including Los Angeles Department of Water and Power and LA Sanitation and Environment), Metropolitan Water District of Southern California, Los Angeles County Sanitation Districts, Las Virgenes Municipal Water District, and West Basin Municipal Water District. 

The full report is available at https://innovation.luskin.ucla.edu/wp-content/uploads/2024/06/Making-the-Most-of-Landmark-Recycled-Water-Investments-in-LA.pdf.

 

The Water Girls

If you're struggling with triple-digit temperatures, think about the honey bees. They need to collect water for their colony to cool the hive so their brood can develop. And for other purposes. Just call them "The Water Girls." Lately the bees have...

A honey bee, its proboscis extended, collects water from the edges of a birdbath. (Photo by Kathy Keatley Garvey)

A honey bee, its proboscis extended, collects water from the edges of a birdbath. (Photo by Kathy Keatley Garvey)

For worker bees: Two's company, three's a crowd, and four is a work party. Bees collecting water from a birdbath. (Photo by Kathy Keatley Garvey)

For worker bees: Two's company, three's a crowd, and four is a work party. Bees collecting water from a birdbath. (Photo by Kathy Keatley Garvey)

'The Water Girls'--six of them--collecting water at a Vacaville birdbath. Note the absence of birds. (Photo by Kathy Keatley Garvey)

'The Water Girls'--six of them--collecting water at a Vacaville birdbath. Note the absence of birds. (Photo by Kathy Keatley Garvey)

A honey bee heading back to her colony after collecting water to cool down the hive. (Photo by Kathy Keatley Garvey)

A honey bee heading back to her colony after collecting water to cool down the hive. (Photo by Kathy Keatley Garvey)

Young orchard water and nutrient management workshops offered in Modesto, Merced, Fresno, Bakersfield

Growers invited to discuss young almonds, pistachios, walnuts, olives and citrus orchards starting May 9

To help growers manage irrigation and nutrients for young and immature orchards, UC Cooperative Extension is offering workshops in Modesto, Merced, Fresno and Bakersfield. 

The workshops will feature presentations by various experts and researchers focusing on best irrigation and nutrient management practices tailored specifically for young orchards in the San Joaquin Valley. They will cover almonds, pistachios, walnuts, olives and citrus.

“Attendees will gain insights into the irrigation and nutrient needs of young orchards, which are different from those applicable to mature orchards, and learn strategies for adjusting these practices as orchards mature,” said Moneim Mohamed, UC Cooperative Extension irrigation and soils advisor for Stanislaus, San Joaquin and Merced counties. “This knowledge aims to ensure healthier tree development, better resource use and more resilient orchards in the face of climate change.”

Growers, certified crop advisers and other agricultural professionals are encouraged to attend. Workshop attendees may request one-on-one assistance from a UCCE farm advisor.

Speakers include UCCE advisors Mohamed, Mae Culumber, Tobias Oker, and Cameron Zuber, UCCE specialist Giulia Marino, Andre Daccache of UC Davis, Charles Hillyer and Shawn Ashkan of Fresno State.

The Young Orchard Irrigation and Nutrient Management workshops will be held in four locations: 

Modesto 

May 9 (8 a.m.–12:30 p.m.)
UC Cooperative Extension, Room HI, 3800 Cornucopia Way

Register at https://ucanr.edu/orchardsmodesto

Merced

May 14 (8 a.m.–12:30 p.m.)
UC Cooperative Extension, 2145 Wardrobe Avenue

Register at https://ucanr.edu/orcharsmerced

Fresno

May 22 (8 a.m.–12:30 p.m.)
Fresno State, 5370 N. Chestnut M/S OF 18

Register at https://ucanr.edu/orchardsfresno

Bakersfield

June 5 (8 a.m.–12:30 p.m.)
UC Cooperative Extension, 1031 South Mount Vernon Avenue

Register at https://ucanr.edu/orchardsbakersfield

Workshops are free and include coffee breaks, lunch, workshop materials along with the presentations. Registration is required. 

These workshops are supported by a grant from California Department of Food and Agriculture and sponsored by Almond Board of California, California Pistachio Research Board, WiseConn Engineering and Irrometer Company, Inc.

 

Sewage to Sustenance

Jules Bernstein - UC Riverside, Senior Public Information Officer

Plant materials that would otherwise become trash may be the key to solving two big problems: diminishing freshwater supplies for farms and diminishing effectiveness of antibiotics. 

On average, agriculture accounts for 70% of global freshwater use. In California, which produces nearly half of all U.S.-grown fruits, nuts, and vegetables, that number rises to 80%. 

The United Nations estimates food production will need to double by 2050. However, water supplies will not increase accordingly. Instead, due to climate change and drought, water resources are quickly shrinking. 

One solution to the increasing need for farm water is to use treated municipal wastewater. There are roughly 16,000 wastewater treatment plants in the U.S., each of them capable of processing up to 10 million gallons every day. 

“It's a huge amount of processed water that's mostly clean and can be used again, but there's a problem,” said Ananda Bhattacharjee, assistant project scientist at the U.S. Department of Agriculture's Salinity Laboratory, based at UC Riverside. 

“This water can contain chemicals of emerging concern, like antibiotics, that are difficult to detect and treat without advanced and expensive instrumentation,” he said. “These instruments also require trained laboratory personnel to operate and maintain.”

Once exposed to the antibiotics in the water supply, soil bacteria immediately start developing resistance to the drugs because they want to survive. “Bacteria are amazing biological sensors,” he said. As the bacteria develop resistance, antibiotics stop working.

Once crops are irrigated with contaminated reclaimed water, plants that get harvested and come to our dinner tables may contain residual antibiotics, resistance genes, and resistant bacteria.

To correct this issue, Bhattacharjee is leading a new, $1 million project testing a low-cost technology to make the reclaimed water safer for agricultural re-use. Funded by the USDA's Agriculture and Food Research Initiative, the project will test how effectively biochar made from various types of discarded plant materials can “polish” the water.

Biochar is a charcoal-like substance made by burning organic material. Burning any organic matter, even wood chips, in limited-oxygen environments retains the mass of the burned substance. The remaining, charred substance is highly absorbent. 

“It's like activated charcoal used in HEPA filters and HVAC systems. Biochar works on the same principal; it adsorbs chemicals present in reclaimed water and allows only clean water to pass through,” Bhattacharjee said. 

Based on this principle, Daniel Ashworth, a soil scientist at the Salinity Laboratory, first built a bench-scale filtration system with biochar for the removal of antibiotics in synthetic wastewater. The results were very promising, with antibiotics removal efficiency of up to 98%. 

“Encouraged by Dr. Ashworth's experiments, we will be designing the larger-scale biochar-based polishing systems for removing residual antibiotics in reclaimed water,” Bhattacharjee said. 

Using biochar polishers could potentially remove the need to detect the antibiotics in reclaimed water, assisting treatment plants that do not have advanced detection or treatment technologies, and cannot afford them. 

Affordability is one of the best features of the biochar system. “As engineers, we try to keep it simple. If we can build something for a dime, we don't want to have to spend a dollar,” Bhattacharjee said. 

For this project, scientists from UC Riverside, the U.S. Department of Agriculture, US Salinity Laboratory, and the University of California's Agriculture and Natural Resources are teaming up to test biochar made from multiple kinds of plant materials left over from agricultural field production. 

To start, they'll collect treated sewage sludge and plant materials such as pistachio shells and date palm leaves which would otherwise be thrown away. These materials will be turned into biochar for designing filtration systems that reclaimed water can pass through. 

Ultimately, the team would like to develop a database of different, inexpensive biochar materials that can all be used for removing harmful compounds from reclaimed water for agricultural reuse, especially crop irrigation.

If the costs remain low and effectiveness remains high, the research team hopes growers will install biochar-based reclaimed water polishing systems on their farms. “That is the major goal of the project, taking this from bench scale to full field scale,” Bhattacharjee said. 

Right now, the whole ecology of fields is changing due to residual antibiotics in irrigation systems. The reclaimed water gets into the soil, earthworms feed on organic matter in the soil, and they develop antibiotic resistance in their guts. Then they may release this resistance through their feces, making additional changes to soil microflora, which keeps the cycle of resistance going.

“We are slowly spiking our own agricultural fields with this resistance,” Bhattacharjee said. “Demonstrating this issue was our first project, Bacteria Wars: episode one. Now we have a technique to remove the antibiotics and resistant bacteria, reducing the antimicrobial resistance spread in agriculture. This is our episode two: Researchers Strike Back.”

 

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Water risks to agriculture: Too little and too much

Water is among the most precious resources on the planet. Some areas don't get enough; some get too much. And climate change is driving both of those circumstances to ever-growing extremes.

Two UC Merced experts in civil and environmental engineering took part in a recent report by the Environmental Defense Fund examining the issue and potential solutions. Associate Professor of Extension Tapan Pathak and Professor Josué Medellín-Azuara co-authored the report, "Scarcity and Excess: Tackling Water-Related Risks to Agriculture in the United States," and wrote the section pertaining to California.

In addition to climate change, disruptive human interventions such as groundwater over-extraction, sprawling drainage networks and misaligned governance are driving up water-related agricultural costs, particularly in midwestern and western states, the researchers found.

The problem is magnified in California, which hosts the largest and the most diverse agricultural landscape in the U.S., Pathak and Medellín-Azuara wrote, with gross revenues from farms and ranches exceeding $50 billion.

"Due to the favorable Mediterranean climate, unique regional microclimate zones, a highly engineered and developed water supply system, and a close connection between producers and research and cooperative extension institutions, California's agricultural abundance includes more than 400 commodities, some of which are produced nowhere else in the nation," the UC Merced researchers wrote.

But the state's varying climate and water needs pose a challenge. Though most of the precipitation falls in the northern part of California, the southern two-thirds of the state account for 85% of its water demand. And all of those crops must be watered in the summer, when there is little, if any, rainfall.

Some of the water comes from snowpack developed through winter storms and stored in reservoirs as it melts. Much of it comes from the Colorado River.

"Substantially less water is captured and stored during periods of drought, imperiling California's water supply and putting agricultural water needs at risk," Pathak and Medellín-Azuara wrote.

Climate change, with increasing periods of drought between excessively wet winters, magnifies that risk.

"Further, the rate of increases in the minimum temperatures in the Sierra Nevada is almost three-fold faster than maximum temperatures, resulting in potential decrease in the snowpack, earlier snowmelt, and more water in liquid form as opposed to snow," the researchers wrote. "According to the California Department of Water Resources, by 2100, the Sierra Nevada snowpack is projected to experience a 48% to 65% decline from the historical average."

Climate change is also expected to affect the availability of water from the Colorado River.

Climate extremes such as heat waves, drought and flooding - giving rises to increased weeds, pests and disease - are already significantly impacting agriculture and the broader economy, Pathak and Medellín-Azuara wrote.

The state's drought from 2012 to 2016 led to about 540,000 acres of fallow farmland in 2015, costing the state's economy $2.7 billion in gross revenue and 21,000 jobs. With the lack of precipitation, farmers increasingly pumped groundwater to irrigate crops, depleting those resources.

The report goes on to recommend policies, programs and tools be developed for agricultural resilience, including:

• Changing land use and crop management practices to support a transition to an agriculture footprint that can be sustained by the available water supplies.
• Increasing farmer and water manager access to important data and innovative technological tools to support their efforts.
• Reimagining built infrastructure and better using natural infrastructure so regions are better equipped to handle weather extremes.
• Developing policy and funding mechanisms to support mitigation and adaptation to water-related risks, avoid maladaptation and ensure food and water security.

"California's innovative agriculture needs to rapidly adapt to more volatile water availability, climate-driven higher water demands, and regulation protecting groundwater reserves, communities and ecosystems," Medellín-Azuara said. "The early adoption of more sustainable practices in agriculture will likely pay off dividends both in the short and long terms."

Added Pathak, "California faces significant challenges related to climate change, but it also presents opportunities for innovations, collaborations and sustained growth. To make agriculture resilient to climate risks, we need to engage in holistic solutions that integrates environmental, social, economic and policy considerations."

 

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