Walk the paved path around the Lafayette Reservoir this month and the skyline looks wrong before you can say why. The tower that has stood at the water's edge since 1929, the one every regular loop-walker has used as a mental finish line for decades, is not where it used to be. The top forty feet are gone. The netting that wrapped it all spring is down. What's left is a squat concrete stump with a crane still parked nearby, and if you haven't done a lap since August, the change will stop you mid-stride.
This is not a story about a reservoir closing for repairs. It stayed open the entire time. It's a story about how a landmark that outlived three generations of Lafayette residents disappeared in about six weeks, why nobody closed the gates while it happened, and what that means for anyone lacing up for the town's biggest fall race.
The Tower Was Never Supposed to Be This Tall
Here's the part almost nobody in Lafayette knows unless they've sat through an EBMUD community meeting: the tower was too tall from the day it was finished. When construction on the dam started in 1927, engineers planned a reservoir nearly three times its current size, with a much taller dam to match. Partway through, the earth-filled embankment started to move under its own weight, and the height got scaled back. The outlet tower, though, had already gone up to match the original, larger plan. So for nearly a century, Lafayette has been looking at a spillway tower built for a reservoir that was never actually finished.
That extra height became a liability after California tightened dam safety rules following the 2017 Oroville Dam crisis. Engineers determined the tower, aging and taller than it needed to be, carried real risk of cracking or breaking in a major earthquake. A failure at the base could compromise the dam itself, and state flood maps show the resulting inundation could reach parts of Lafayette and Walnut Creek, including a K-8 school, the police department, and the Lafayette BART station.
That's the seismic case for cutting it down. It's also why the debate over the design ran for years before anyone touched the concrete, with a citizens committee pushing EBMUD to consider alternatives that would preserve the tower's full height. EBMUD reviewed those alternatives and determined they wouldn't meet seismic requirements, and by early 2025 the agency had a deadline from the state's dam safety division to move forward.
What Actually Disappeared This Summer
Once approved, the work moved fast. Crews began removing the tower's roof and operating house in early July 2026, then started saw-cutting the concrete rings off the tower stem, about a dozen sections, each roughly three feet tall, using a crane mounted on a floating barge. By August 21, the tower had reached its new, shortened height. What's happening now is less dramatic but still visible: crews are building new corbels and a floor inside the shortened structure to support a new metal operating house, designed to echo the tower's original look, which is scheduled to go in by November 2026.
The whole tower and conduit retrofit, along with related tree removal and access road widening, is estimated at $14 million. Full commissioning and testing won't wrap until fall 2027, but the visible, skyline-altering part of the work is largely done. If you're picturing the reservoir as still under some kind of long construction siege, the more accurate picture is that the biggest visual change already happened, and what's left is quieter finishing work plus one more construction season next spring for underwater gate work.
The Reservoir Never Closed, and That Was the Point
Given the scale of the project, it would be reasonable to assume the reservoir shut down for stretches this year. It didn't. EBMUD structured the work specifically to avoid that. Construction has been limited to weekdays, so weekend regulars, the people who show up for a Saturday morning loop or a Sunday picnic, have largely been insulated from it. There are no planned vehicle closures tied to the tower project itself.
The routing decision is the detail most residents probably haven't clocked: all demolition debris and construction traffic uses the Acalanes Road onramp to and from Highway 24, meaning trucks never pass through downtown Lafayette. That's not an accident. It's a deliberate choice to keep a $14 million infrastructure project from ever touching Mt. Diablo Boulevard traffic.
What you will notice on the ground is more mundane. Visitors on the paved Lakeside Nature Trail may encounter crews moving equipment across the path near the barge ramp, with flaggers managing pedestrian and vehicle flow at the main entrance and along the trail itself. Expect occasional ten to fifteen minute delays if you're walking through at the wrong moment. Earlier this year, picnic site reservations were paused between February and July because of construction staging, though EBMUD indicated it would reopen dates as the schedule firmed up. If you're planning a group picnic this fall, it's worth checking current availability before you count on a specific spot.
There's also a second, less visible project running in parallel: EBMUD is replacing the aging wastewater system and sewer piping across the recreation area, a job scheduled from fall 2025 through fall 2026. It doesn't get the headlines the tower does, but it's part of why crews and equipment show up in more places around the park than just the tower itself.
The Race Still Runs Right Through It
Here's where the timing gets interesting. The Lafayette Res Run for Education, the city's marquee fall race, is set for Sunday, October 18, with the companion Reservoir Challenge, a virtual lap event around the 2.7-mile paved trail, running October 10 through 17. That puts both events squarely inside the window when the new operating house is still being finished and wastewater work is still active nearby.
Nobody is rerouting the race because of it. The event has run for more than three decades as a genuine neighborhood fundraiser, not a spectator race, and its economics are worth pausing on. In 2025 alone, it raised $37,611.32 for local schools, with Burton Valley Elementary pulling in the most registrations, Happy Valley showing the biggest year-over-year improvement, and smaller totals going to Stanley Middle School, Acalanes High, Campolindo High, and several others. Over the past five years, the race has funneled more than $178,000 directly to Lafayette-area school programs. That's not abstract civic spirit. It's PTA budgets and classroom supplies, built entirely on a Sunday morning loop around a reservoir that, this year, looks different than it has in a century.
Two Loops, Two Different Falls
If you're deciding how to spend a weekend morning at the reservoir this season, the two trail options offer genuinely different experiences right now. The paved 2.7-mile Lakeside Nature Trail hugs the shoreline and is where you'll actually see the construction activity, the barge, the shortened tower, the occasional flagger. The unpaved 4.7-mile Rim Trail climbs above it all, with views toward Mount Diablo and the East Bay hills, and largely avoids the work zone entirely if you'd rather not think about cranes on your hike.
Dogs are welcome on both, leashed and under six feet at all times, and if your walk ends with a stop for treats or a grooming appointment, Big Woof, the pet boutique and spa that opened in downtown Lafayette in 2025, sits a short drive from the reservoir entrance. It's the kind of small, specific detail that makes a Saturday routine feel like a routine rather than a tourist itinerary.
What This Actually Means for Your Next Lap
The headline most people will remember is "the tower is being fixed." The more accurate version is that the tower Lafayette has looked at for a hundred years is already gone, replaced by something forty feet shorter that most residents haven't seen in person yet. The reservoir stayed open through all of it. The race is happening on schedule. The only thing that's permanently different is the skyline you'll see when you round the bend past the dam.
If you haven't walked the loop since midsummer, this is the season to go look. The tower won't get any taller, and by the time the operating house goes in this November, the "new normal" silhouette will be the only one anyone under thirty has ever actually seen at full height.
Kailani Kimoto keeps close tabs on what's actually changing across Lafayette, Rossmoor, and the rest of the Lamorinda area, from construction timelines to festival calendars, because that's what paying attention to a neighborhood really looks like. Explore more local updates and get in touch anytime you want the same kind of on-the-ground read on what's happening next.
