San Elijo Lagoon Is Running Clear This Fall. A Sand Bar Decides How Long It Lasts.

Have you looked over the rail of a Nature Bridge lately? This month Nature Collective reported that people who have walked San Elijo Lagoon for decades are seeing small schools of fish below the surface, stingrays gliding through the channels and large striped mullets diving, with what the group called "unprecedented visibility."

That clear water depends on one thing at the beach end of the lagoon. Ocean water has to keep reaching the channels through the inlet under Highway 101, and sand has to stay out of its way. Through the summer, the inlet stayed open. The budget that kept it open is spent until spring. This winter will decide what the lagoon looks like for the rest of the season.

What the October Water Is Showing

In its October 9 post on the lagoon's clear water, Nature Collective credits the San Elijo Lagoon Restoration Project. The water always shifts with the tides. Incoming tides carry in clear ocean water with little sediment, and runoff from inland carries more. The restoration tripled the lagoon's tidal prism, which is the volume of water that moves between the lagoon and the Pacific in one tidal cycle. More ocean water now flushes through every day, so the lagoon stays much clearer overall than it used to.

The restoration got there by widening and deepening channels to carry up to three times more tidal flow. It also added the pedestrian bridges that link the Nature Center Loop Trail to the Pole Trail. Nature Collective says those bridges are the best place to look into the water, because they put you right over the channel with a clear, low-glare view down.

The same post names the two things that cloud the water again. One is rain. The lagoon takes in runoff from the whole Escondido Creek watershed, and stormwater muddies the channels until the daily tides clear them out. The other is the inlet closing, when sand builds up at the beach and cuts the channel off from the ocean's tides. The ocean tide is what makes the water clear, and the inlet is the only way it gets in.

The Sand Under the Railroad Bridge

Nature Collective has posted updates on the inlet over the past year:

• November 14, 2025. Nature Collective warned the inlet might close. Sand had refilled the channel after the last dredging, and the lagoon was having trouble flushing water out. That weekend, a forecast swell of 6 to 8 feet could have pushed in enough sand to block the channel. A forecast of up to 2 inches of rain might have sent enough Escondido Creek flow to push some sand back out.
• February 2026. A winter storm briefly broke through the sand on its own, but the channel stayed mostly blocked.
• March 17, 2026. With the inlet closed again, Nature Collective scheduled its annual land-based excavation to start March 19. The seven-day job worked west of the railroad bridge, and the sand went to rebuilding part of the Cardiff Living Shoreline dunes south of the Charthouse Restaurant.
• Summer 2026. That excavation removed more than 22,000 cubic yards of sand, and the inlet stayed open all summer.
• September 1, 2026. Nature Collective reported that new sand had built up over the summer, reaching under the railroad bridge toward the Nature Center. The March work had used up the group's partial endowment for 2026 maintenance, so clearing this new sand depends on outside funding.

The September update had good news too. State and federal agencies have approved an adaptive management plan that lets crews use land equipment to clear sand east of the railroad bridge. SANDAG funds the plan through the restoration project, which was mitigation for the expansion of the railroad and Interstate 5. Once the money is secured, the full sand removal will take about two months.

Nature Collective's preferred window for that work is April and May 2027, after storm season. If the inlet closes this fall or in mid-winter, the group may do a short 1- to 2-day emergency clearing, if it's needed and if funding allows. The September update was the most recent report of the inlet being open. The clear water seen in October came weeks after it.

Why This Winter Could Go Either Way

The September update calls El Niño "the ultimate wild card," and gives two ways it could play out. Heavy rain over the watershed could work like a natural pressure washer, sending enough flow down the channels to keep the inlet open. Large ocean swells without much inland rain could push more sand into the inlet with nothing to flush it back out.

Either way, a big storm will cost some visibility for a while. Rain that helps keep the inlet open also sends cloudy runoff into the channels until the tides clear it. A swell that closes the inlet stops the ocean water that keeps the lagoon clear. The clear water reported in October happened in the calm stretch before any of that. Nature Collective says it is watching the lagoon closely and will adjust its plans as conditions change.

The habitat matters as much as the view. Nature Collective writes that when the inlet closes, water quality drops and rising water can damage the vegetation that endangered species need. One example is California cordgrass, the preferred habitat of the endangered Ridgway's Rail.

Timing a Clear-Water Walk

Nature Collective's post explains when the water is clearest. All of these have to line up:

1. An incoming tide. Rising water brings in the clear ocean water. Check a tide chart before you leave.
2. A high sun. Midday light reaches farther down into the water.
3. Calm wind. A smooth surface means less glare and fewer ripples hiding what's underneath.
4. A dry stretch. After rain, runoff clouds the channels until the tides clear it again.
5. An open inlet. Without it, none of the steps above help much.

In late fall, a calm late morning with the tide coming in is your best bet, with a high sun and little wind on the water. Before you go, check the San Diego County Parks notices page, because the County warns that San Elijo trails can close during storms or high tides.

Where to Stand

The best viewing spots are the two Nature Bridges, called the Buhr and Martin bridges. They cross wetland channels on the way to the Nature Center.

From the Nature Center

The Nature Center Loop Trail starts at 2710 Manchester Ave. in Cardiff-by-the-Sea and is open sunrise to sunset. San Diego County Parks lists the Nature Center as open every day from 9 a.m. to 5 p.m. According to the September update, the summer sand had reached under the railroad bridge toward the Nature Center, so that end of the trail shows the inlet story most directly.

From Rios Avenue

The Rios West Trail runs from the Rios Ave Trailhead to the Nature Center Loop and crosses both the Martin and Buhr bridges. County Parks lists 900 North Rios Ave. in Solana Beach as the address for the Annie's Canyon Trailhead.

From Via Poco

On the Cardiff side, the Via Poco trailhead is mapped at 2550 Via Poco. That route heads to Annie's Canyon and crosses the suspension bridge under I-5. The suspension bridge and a nearby rail pedestrian undercrossing were built under SANDAG's Build NCC program, which lists both as completed projects. They are separate from the Buhr and Martin Nature Bridges.

November on the Lagoon Calendar

Nature Collective has several guided and volunteer mornings on the calendar this month, and every one requires registration:

• Wednesday, November 4, 9 a.m. to noon. A free Volunteer Restoration Event to remove invasive plants and plant natives. Open to ages 6 and up, with minors joined by a guardian. The meeting spot is shared ahead of time.
• Saturday, November 7, 10 to 11:30 a.m. A free Discovery Tour on the Nature Center Loop Trail at 2710 Manchester Ave., for ages 9 and up.
• Saturday, November 14. A Wildlife Tour focused on late-fall shorebirds, ducks, songbirds and raptors, including White-crowned Sparrows, Yellow-rumped Warblers and Northern Harriers. The meeting point is emailed to registrants. The listing shows the time as "9:00-1:00 am," so check the end time with Nature Collective before you plan your morning around it.
• Saturday, November 21, 9 a.m. to noon. A second free Volunteer Restoration Event on the same terms as November 4.

The calendar continues into December. There is a free Discovery Tour on December 5 from 10 to 11:30 a.m. on the Nature Center Loop Trail, and a free Wildlife Tour on December 12 from 9 to 11 a.m. By then the winter's first big storm or swell may have changed what you can see from the bridges.

FW Property Group is based in Cardiff-by-the-Sea, the same community as the Nature Center on Manchester Avenue. If you own near the lagoon and want to know how that location shows up in today's numbers, request your free home valuation.