News
When your local reflecting pool or pond turns green with algae, don’t reach for chemicals – nature has better solutions
When ponds and reflecting pools turn green with algae, chemical “quick fixes” often fail. Here’s how nature-based solutions like Daphnia and aquatic plants can restore water quality longer-term.
Eric Palkovacs, University of California, Santa Cruz
When the Lincoln Memorial Reflecting Pool turned green with algae just days after a US$15 million renovation, the U.S. government scrambled for chemicals and expensive technical solutions to fix the iconic landmark.
Trying to kill algae with chemicals is a common response when community ponds or other water features go green. But as a scientist who studies freshwater ecology, I can tell you there are better solutions that cost far less, last longer and carry less risk of harm to pets and wildlife.
Rather than battling against nature, these alternatives work with nature for long-term solutions. https://www.youtube.com/embed/nkqBQ1r0Kto?wmode=transparent&start=0 If you need to treat a slimy, green, algae-filled body of water, you shouldn’t drain and refill the water, which resets the entire ecosystem. Instead, one solution is quite simple and relies on nature, not chemicals.
What went wrong on the National Mall
The algal bloom that turned the Reflecting Pool a vibrant green shouldn’t have been a surprise.
The pool is big, more than a third of a mile long and around 165 feet wide. But it’s shallow, meaning it warms up quickly in the sun. When it was repainted “American flag blue” during the renovations in spring 2026, the new color darkened the pool, and darker colors absorb more heat.
On top of those conditions, the pool was refilled with water from the nutrient-rich tidal basin of the Potomac River. The combination of warm water and nutrients created prime conditions for algae to bloom, turning the water pea soup green.
As the national conversation over the Reflecting Pool shifts to political finger-pointing, an important environmental question deserves careful scrutiny: What is the best approach to maintain water quality in a case like this, whether for a national monument or a community water feature or pond?
Trying to chemically or mechanically remove algae can damage the structure of a water feature and may harm species in the water that could actually help solve the problem.
Importantly, chemical and mechanical solutions are only temporary fixes. When the Reflecting Pool is drained and filled again, there’s a good chance that algae will bloom again.
Natural algae control
Limnologists – scientists like me who study inland water bodies – have spent many decades learning why lakes and ponds turn green and how to clear them up.
Often, nutrient-rich waters fueled by fertilizer runoff from farm fields or sewage from cities are the sources that stimulate algal growth.
However, natural ponds also host grazing zooplankton, which eat algae. For example, a type of zooplankton called Daphnia, known as water fleas because of the way these tiny crustaceans swim, can control algae by consuming it before it becomes a pea soup nuisance. Thus, a thriving Daphnia population can help maintain good water quality in a lake, pond or community water feature, even when nutrient levels spike.
In addition to being highly effective grazers, Daphnia have another superpower – they can evolve rapidly. Urban waterbodies are often harsh environments with a variety of challenges, including high temperatures, low levels of dissolved oxygen, and pollutants. Daphnia can adapt to tough conditions, making these creatures an ideal source of algae control in many urban ponds.
Rooted aquatic plants are also useful for algae control in ponds because they absorb nutrients. Thus, shallow ponds with thick beds of aquatic plants can often resist algal blooms when nutrient levels rise.
Why draining might not be the best solution
One downside to draining and refilling a pond or urban water feature to try to clean it is that doing so resets the aquatic ecosystem, erasing the signature of any past evolution that has taken place.
Imagine Daphnia in a shallow pond that experiences periodic heat waves throughout the summer. Through repeated exposure to high temperatures, natural selection favors heat-resistant genotypes that can thrive in an urban pond.
Daphnia and other grazing zooplankton can also evolve resistance to some types of cyanobacteria, also known as blue-green algae, which produce compounds that are toxic to people and pets. Daphnia that evolve resistance to those toxins can help control harmful cyanobacterial blooms.
If a Daphnia population that evolved to tolerate warm temperatures, low oxygen levels or cyanotoxins is removed, the new population likely won’t be ready to handle those local challenges. This evolutionarily naive population will perform poorly in its new environment, reducing its effectiveness at controlling algal blooms.
As a result, traditional mechanical and chemical approaches may actually work against the goal of minimizing algae in ponds and other water features.
Nature-based solutions
The use of Daphnia to control algal blooms is just one example of solving environmental challenges with nature-based solutions.
Growing urban forests to provide cooling and improve air quality to help reduce the need for more energy-intensive air conditioning is another example. Maintaining urban wetlands can help reduce flooding, protect property and recharge groundwater more effectively and for less money than building and maintaining levees. Coastal marshes similarly reduce erosion, buffer storm surges and support fisheries.
All these urban ecosystems protect biodiversity and support human health and well-being.
From national landmarks to city parks and backyard ponds, projects of all sizes can take advantage of nature-based solutions. While each specific project is unique, some general principles apply.
Ecosystems are most resilient when they are diverse and connected. So, it is beneficial to use a variety of species and genotypes and provide corridors that support the movement of organisms and their beneficial genes.
Urban climates are changing rapidly, so it helps to use species and genotypes that will thrive under future conditions, including rising temperatures.
Not every solution has to be engineered
The hubbub over the Reflecting Pool holds a mirror up to assumptions about how to solve pressing environmental challenges. The idea of just engineering one’s way out of any environmental crisis has limits.
Understanding ecology and nature’s mechanisms of ecosystem resilience can achieve sustainable solutions that benefit both nature and people.
Eric Palkovacs, Professor of Ecology and Evolutionary Biology, University of California, Santa Cruz
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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Daily News
Major Construction Begins on Metro’s East San Fernando Valley Light Rail Line
LA Metro has moved the East San Fernando Valley Light Rail Transit Project into major construction. The 6.7-mile Van Nuys Boulevard line will add 11 stations, connect with the G Line and regional rail services, and is now targeted for completion in early 2032.
After years of utility relocation and planning, LA Metro is moving into major construction on a new rail line along Van Nuys Boulevard. The milestone also comes with a revised early-2032 completion target.
LA Metro has officially marked the beginning of major construction on the East San Fernando Valley Light Rail Transit Project, moving one of the region’s most important rail projects from preparatory work into full-scale construction.
Metro held a groundbreaking ceremony on October 19, 2026, for the 6.7-mile line, which will run along Van Nuys Boulevard from the G Line busway north to San Fernando Road in Pacoima. The project will add 11 light-rail stations serving Van Nuys, Panorama City, Arleta and Pacoima.
This was not the project’s first groundbreaking. Metro held an earlier ceremony in December 2022 when crews began relocating utility infrastructure. The new milestone is more consequential for riders: the major-construction phase covers the guideway, stations, traction-power substations, rail systems and a maintenance and storage facility.
From utility work to a new rail corridor
The project has spent several years in utility relocation, property acquisition, design and other early work. Metro’s current construction timeline shows major work continuing from 2026 through 2032, with phased traffic changes and K-rail installations expected along Van Nuys Boulevard.
When completed, trains are expected to operate every seven to 10 minutes during peak periods. The line will connect directly with the G Line and provide access to the Van Nuys Metrolink and Amtrak station. It is also expected to become an important transfer point for the future Sepulveda Transit Corridor and a planned Metrolink station in Pacoima.
The corridor already has a substantial transit market. Metro reported that bus Lines 233 and 761, which serve Van Nuys Boulevard, recorded nearly 20,000 boardings in September 2026. The agency also says approximately 19 percent of households in the project area lack access to a car, compared with about 8 percent countywide.
Those figures help explain why this project matters beyond its construction footprint. It is intended to give residents in some of the Valley’s most transit-dependent communities more reliable access to jobs, schools, healthcare and the wider regional transit network.
The opening target has moved to 2032
Metro’s current project page lists an estimated completion date of early 2032. That is later than the 2031 opening forecast the agency publicized when it celebrated an $893-million federal grant in September 2024. Earlier plans were more optimistic still: when utility work began in 2022, Metro said the first segment could open between 2028 and 2030.
The project’s financial scale has also grown clearer. In May 2026, the Metro Board established a life-of-project budget of approximately $3.999 billion and authorized the next phase of its progressive design-build contract with San Fernando Transit Constructors, a joint venture of Skanska and Stacy and Witbeck.
That authorization increased the construction contract’s value to roughly $2.431 billion. Funding for the larger project combines federal, state and local sources, including revenue from Los Angeles County’s Measure M transportation sales tax.
Rail returns to Van Nuys Boulevard
The East San Fernando Valley line will restore passenger rail to Van Nuys Boulevard for the first time since Pacific Electric ended streetcar service there in 1952. It will also become the first major new Metro rail project in the San Fernando Valley since the subway reached North Hollywood in 2000.
The historical parallel is significant. Van Nuys Boulevard once developed around electric railway service before the region shifted heavily toward automobiles and buses. Metro is now rebuilding rail in the same broad corridor, but as part of a modern network designed to connect local riders with bus rapid transit, regional rail and future high-capacity projects.
The current project ends in Pacoima. Metro continues to study a separate 2.5-mile northern extension that would reach the Sylmar/San Fernando Metrolink station. That extension is not included in the segment now entering major construction.
For riders, the October groundbreaking does not mean trains are imminent. Several years of disruptive and technically complex work remain, and the schedule has already moved beyond earlier forecasts. Still, it represents a tangible transition: the East San Fernando Valley line is no longer primarily a planning exercise or utility-relocation program. Metro has begun building the infrastructure that will carry trains.
That makes this a major step in Los Angeles County’s long effort to restore frequent rail transit to communities that lost it generations ago—and another chapter in The Long Track Back.
Primary sources
- LA Metro: Major construction will soon be underway
- LA Metro project page: East San Fernando Valley Light Rail Transit
- LA Metro Board meeting, May 28, 2026 — project budget and contract authorization
- LA Metro: $893 million federal grant announcement, September 6, 2024
- LA Metro: Advanced utility-work groundbreaking, December 2, 2022
This article is part of The Long Track Back, STM Daily News’ continuing coverage of how Los Angeles is rebuilding and expanding a passenger-rail network after decades of automobile-centered grow
For generations, the Santa Monica Pier sign has marked the start of a day at the beach. Now, the familiar blue neon landmark is preparing for a journey of its own.
Santa Monica scheduled removal of the 1941 sign for October 20–22, with shipment to Las Vegas anticipated October 26. The timetable is subject to change, according to the city’s October 19 announcement.
The temporary removal accompanies replacement of the aging bridge connecting Ocean Avenue to the pier. It also creates an opportunity to preserve the historic sign.
YESCO will restore it at its Las Vegas facility. The company’s experience includes work on the “Welcome to Fabulous Las Vegas” sign.
Crews will repair neon tubing, treat rust, repaint components and address structural needs while retaining historic features. The sign will remain in secure storage during bridge construction.
Once the project is finished, it will return above the new bridge at a slightly greater height for visibility and vehicle clearance. The city’s latest announcement targets project completion by 2028, ahead of the Los Angeles Olympics and Paralympics.
Meanwhile, visitors can photograph a lighted, half-scale replica near Pier Burger.
For anyone who associates that glowing arch with Southern California memories, its absence will be noticeable. The restoration is intended to ensure future generations can make memories beneath it, too.
Source: City of Santa Monica — October 19, 2026 announcement
Related Links
- City of Santa Monica: Official sign restoration announcement — October 19, 2026. Primary source for removal dates, shipment to Las Vegas, YESCO’s restoration work and the sign’s planned return.
- Santa Monica Daily Press: Sign restoration during bridge rebuild — October 20, 2026. Additional local reporting on the project and visitor access.
- LAist: Sign removal and how to watch — Reporting on the removal schedule and public viewing opportunities.
Follow more Southern California stories at STM Daily News.
Automotive
Slate Truck Gets Real: First Experience Center Opens Ahead of Planned Deliveries
Slate Auto’s first permanent Experience Center gives consumers an up-close look at its customizable electric truck ahead of planned customer deliveries.
Slate Auto’s new Chicago location gives prospective buyers a permanent place to see the minimalist electric pickup, explore customization options and learn about demo opportunities—but it is not yet proof that customer deliveries have begun.
CHICAGO — October 20, 2026 — The Slate Truck is moving out of computer renderings and temporary roadshow stops and into a permanent retail setting. Slate Auto opened its first Experience Center on October 15 at 1053 W. Grand Avenue in Chicago, giving consumers a year-round location to get an up-close look at the company’s highly anticipated electric pickup.
The Near West Side facility occupies a former Tesla location and includes showroom, retail and garage space, along with electric-vehicle charging infrastructure. For Slate, the opening represents an important step in turning strong online interest into a more tangible buying experience as the startup works toward launching its first vehicle.
Visitors can examine the truck’s compact dimensions, deliberately simple cabin and accessory-driven design in person. The center also showcases Slate’s personalization strategy, including exterior wraps, add-on accessories and digital design tools intended to let owners configure the truck around their needs.
Slate has also promoted demonstration opportunities connected with the location, although availability may be limited or appointment-based as the company continues to prepare its fleet. Early media access included passenger rides rather than unrestricted customer test drives, so prospective visitors should confirm current availability before making a special trip.
Why the Chicago opening matters
Until now, most consumers have encountered the Slate Truck through online reservations, media coverage or temporary appearances. A permanent showroom gives buyers a chance to judge details that are difficult to evaluate on a screen, including seating position, bed access, cabin materials and the overall size of the vehicle.
That is especially important for a product built around an unconventional value proposition. Slate is promoting a basic two-seat, two-door electric truck with manual crank windows and no factory-installed infotainment screen or stereo. The company’s strategy is to keep the starting price low and let buyers add features later through accessories and conversion kits.
The physical location also gives Slate a place to explain that approach directly. Rather than presenting the truck as an unfinished vehicle, the company can demonstrate how its modular accessories, wraps and planned SUV-style conversion components are meant to expand the vehicle’s usefulness over time.
Chicago is a logical first market for that effort. The city offers access to a large Midwestern customer base and is within the broader region of Slate’s planned manufacturing operation in Warsaw, Indiana. Reusing a former Tesla store also gives the startup a space already suited to displaying and servicing electric vehicles.
The roadshow continues beyond Chicago
The Experience Center is opening as Slate expands its public demonstration schedule. The company’s events calendar lists a Boston-area demo ride event from October 21 through October 25 at The Shops at Chestnut Hill, followed by an appearance at RADwood in Alameda, California, on October 24 and a New Jersey demo ride event in Freehold from October 28 through October 31.
Slate also lists future stops in Washington, D.C., Raleigh, Atlanta, Miami and Orlando. Together, the permanent Chicago center and the traveling events suggest the company is moving into a broader customer-education phase ahead of planned deliveries.
What has—and has not—changed
The showroom opening does not change Slate’s headline pricing or range claims. The truck is still advertised with a base price of $24,950 before taxes, registration and destination charges. With the currently listed $1,450 destination fee, the entry price would be approximately $26,400 before other costs or optional equipment.
Slate also continues to advertise an estimated range of up to 205 miles. That figure remains an estimate rather than a final EPA-certified rating.
Most importantly, Slate has not publicly confirmed that regular customer production has started or that the first retail deliveries have occurred. Limited deliveries have been reported as possible before the end of December 2026, while many reservation holders may receive later delivery windows in 2027. The Chicago opening is therefore a commercialization milestone, not a manufacturing milestone.
For customers and industry observers, the next major signals will be the start of production at the Warsaw factory, final specifications and EPA range ratings, and confirmed handoffs to paying buyers.
The bottom line
Slate Auto now has a permanent place where consumers can see and evaluate its unusually simple electric truck. That makes the product feel more real and gives the company a platform to explain a customization-heavy business model that may be unfamiliar to traditional truck buyers.
Still, the biggest questions remain unanswered. Opening a showroom demonstrates progress in marketing and customer engagement; producing vehicles at scale, holding the promised price and delivering a 205-mile truck to reservation holders will determine whether Slate can convert enthusiasm into a viable automotive business.
Sources and more information
- Slate Auto events and demo schedule
- Electrek: Slate opens its first Experience Center in Chicago
- Autoblog: Slate opens its first U.S. showroom
- Slate Auto
Category: Consumer Corner / Automotive
