If you've circled the reservoir loop anytime since late summer, you've probably done a double take. The tower that has poked up out of the water since before your grandparents were born is missing its top third. No operating house. No familiar silhouette against the hills. Just a stub of concrete rising out of the lake, wrapped in netting, looking less like a landmark and more like something a barge crew abandoned mid-project.
Here's the part most people walking the Lakeside Nature Trail this month don't quite have straight: the dramatic-looking work, the part that changed the skyline in a matter of weeks, is basically done. The project that caused it is nowhere close to finished. And there are actually three separate East Bay Municipal Utility District projects converging on the reservoir this year, only one of which permanently changes what the tower looks like. If you've been assuming "the res will be weird for a while, then back to normal," that's not quite the shape of what's coming.
An engineering mistake wearing a landmark's clothes
The tower's extra height was never intentional. When EBMUD poured it in 1929, the dam it served was originally planned to be taller. The dam height changed partway through construction, and nobody went back and shortened the tower to match. The result sat there for close to a century: a spillway and drain structure built roughly 40 feet taller than the finished reservoir actually required.
That accident of engineering is what gave Lafayette its odd, charming, slightly out-of-scale landmark. It's also the reason EBMUD now says the tower poses a real seismic risk. A structure that tall, aging, connected to the dam's only drain system, is more likely to crack or buckle in a major earthquake than a shorter one would be.
Why 2017 changed the math
For decades, the extra height was a quirk. It became a mandate after the 2017 Oroville Dam crisis, when California's Division of Safety of Dams tightened safety requirements across the state. State regulators classify the risk downstream of Lafayette as extremely high, and their flood mapping shows a tower failure could send water toward a K-8 school, the Lafayette Police Department, and the Lafayette BART station, along with parts of Walnut Creek. EBMUD spokesperson Christopher Tritto put it plainly to CBS News this July: the taller and older the tower gets, the more likely it is to crack under a big enough quake.
The fight that slowed it down but didn't stop it
None of this went unchallenged. A group of Lafayette residents, all professional structural engineers and architects, formed a Citizen's Technical Advisory Committee and spent more than two years arguing the tower could be retrofitted at its existing height. They gathered over 100 signatures from reservoir walkers who had no idea the shortening was even being considered. The Lafayette City Council formally asked EBMUD to reconsider. EBMUD delayed construction by more than a year and spent over $500,000 reevaluating the committee's alternative design.
DSOD reviewed both approaches and ultimately upheld EBMUD's shortened design as the one that satisfied state safety requirements. That's the version now under construction, at a project cost EBMUD puts at roughly $14 million, covered by ratepayers.
What's actually finished, and what isn't
Here's where the timeline gets useful if you're trying to figure out how much longer your walks will sound like a construction site.
| Phase | Status as of September 2026 |
|---|---|
| Operating house and roof removal | Complete, finished in July |
| Cutting 13 concrete rings off the tower stem | Complete, tower reached its new shortened height around August 21 |
| New metal operating house construction | Underway, targeted for completion by November 2026 |
| Underwater slide gates and electric motor operators | Not started, scheduled for spring 2027 once the seasonal environmental work window reopens |
| Full tower testing, commissioning, and return to operational status | Targeted for fall 2027 |
The visually dramatic part, the crane on a barge sawing through concrete rings, already happened. What's left is slower and mostly out of sight: finishing the new metal top, then waiting out the fall closure of the in-water work window, then coming back next spring to install the underwater hardware that actually lets the tower do its job as a spillway. If you were hoping the res would look and feel finished by the holidays, plan on another year.
Three projects, not one
Part of why the reservoir has felt under construction for so long is that the tower work isn't the only thing happening. EBMUD is running three separate projects in Lafayette this year.
The tower retrofit is the one changing the skyline. Separately, a Wastewater Collection System Improvements project has been replacing the aging sewer lift station and piping that serves the Visitor Center, Ranger Residence, and Maintenance Building, running from fall 2025 through fall 2026. That's the project responsible for the equipment and crews you'll see near the Lakeside Nature Trail and the barge ramp area, independent of the tower work. A third project, upgrades at the Lafayette Water Treatment Plant, is affecting a different trail entirely: a portion of the Walter Costa Trail has been temporarily closed for that work, so if you stick to the main loop you likely haven't noticed it at all.
Lumping all of this into "the res is under construction" isn't wrong, but it flattens three different timelines into one, and it's part of why the disruption feels open-ended even after the most visible piece wraps up.
What this actually means for your next lap
A few practical notes if you're planning to use the reservoir this fall:
- Expect occasional 10 to 15 minute pedestrian delays where flaggers manage crews moving equipment across the Lakeside Nature Trail toward the exit road.
- Debris from the tower demolition is being trucked out via the Acalanes Road onramp, which means construction traffic isn't routing through downtown Lafayette.
- Picnic site reservations were unavailable between February and July 2026 while construction ramped up. EBMUD has said it expects to reopen select reservation dates as the schedule firms up, so it's worth checking before you plan a group outing.
- The Lafayette Res Run for Education returns October 18, with the 5K starting at 8 a.m., the 10K at 8:15, and a 2-mile fun run at 8:45. The companion Reservoir Challenge, a self-paced version of the 2.7-mile paved loop, runs October 10 through 17, but the reservoir closes to Challenge participants on race day itself to make room for the 10K.
EBMUD has also fielded enough questions about the original tower's fate that it's said it plans to create some kind of commemorative token from the salvaged pieces, including a window dating to the late 1920s, though a formal plan hadn't been announced as of the utility's most recent update.
The tower will look mostly the same when this is all done, just shorter and, EBMUD says, safer. What won't be the same is how long you should expect the reservoir to feel like a work zone. The dramatic cut already happened. The quieter, slower year is just getting started.
If you're thinking through a move in Lafayette, Orinda, Moraga, or anywhere else in Lamorinda and central Contra Costa, and you'd rather talk to someone who actually walks these trails than someone reading a listing sheet, Lauren Deal would love to hear from you. Let's Connect.
