Dave Van Mouwerik - Estero Bay, California

China Harbor to Spooner's Cove

14.4 miles (23.2 km)

8 hours, 18 minutes on August 16, 2015

Observed and documented by Evan Morrison

First swim of Estero Bay width



  • Name: Dave Van Mouwerik
  • Age on swim date: 57
  • Nationality: United States
  • Resides: San Luis Obispo, California

Support Personnel

Swim Parameters

Route Definition

Crossing of Estero Bay from China Harbor (near Point Estero) to Spooner’s Cove (near Point Buchon).

  • Route Type: straight-line, point-to-point, clearing the water at start and finish.
  • Minimum Repeatable Route Distance: 14.4 miles (23.2 kilometers)

estero bay panorama
Estero Bay, San Luis Obispo County, California. Photo courtesy of Wikimedia Commons.


China Harbor, on private property near Harmony Headlands State Park. 35.463733 N, 120.993098 W.

china harbor
Photo by Evan Morrison.


Spooner’s Cove in Montaña de Oro State Park. 35.273635 N, 120.888824 W.

spooners cove


Marathon Swimmers Federation Rules of Marathon Swimming - standard conduct and equipment, no exceptions

Swim Data

  • Start Time: Sunday, August 16, 2015. 06:27 local time (Pacific Daylight)
  • Finish Time: 14:45
  • Elapsed Time: 8 hours, 18 minutes, 24 seconds
  • Conditions Summary:
    • Sea Temp: 59-60F
    • Air Temp: 62-70F
    • Wind: 0-10 kt
    • Waves: flat to 4-6 ft
  • Historical Claims: First known trans-Estero Bay swim.

GPS Track

Recorded by Garmin Fenix 2 worn by observer.
Frequency: 30 minutes

Download Data:

Hourly Progress

Hour Latitude Longitude Meters Total Km Km to Finish
0 35.464 -120.993 - 0.0 23.2
1 35.435 -120.983 3322 3.3 19.9
2 35.408 -120.968 3322 6.6 16.6
3 35.384 -120.955 2879 9.5 13.7
4 35.364 -120.941 2642 12.2 11.0
5 35.340 -120.928 2828 15.0 8.2
6 35.318 -120.922 2528 17.5 5.8
7 35.297 -120.911 2537 20.1 3.3
8 35.277 -120.895 2645 22.7 0.7
8:18 35.274 -120.889 695 23.4 0.0

Observer Report

Background: Dave and I serve together on the Santa Barbara Channel Swimming Association board of directors. We had been planning this swim together, across what (as far as we knew) was a previously unswum stretch of ocean. Our plan was for one of us to swim, with the other observing; and, after a rest day, reverse roles. Unfortunately, my planned swim date was scuttled due to weather. Mother Nature settled down in time for Dave’s date, however, so I was happy to observe him complete the first known swim across Estero Bay, California.

Sunday, August 16, 2015, 0429 hours. Swimmer, captain, observer, and crew convene at the dock of the Bonnie Marietta along Morro Bay’s Embarcadero. Everyone is present and accounted for. Under clear skies and a waxing crescent moon, the air is still – and the swim is on. We load supplies into the large work area of Bonnie’s stern, and push off shortly thereafter.

[0455] Capt. Mark exits Morro Bay harbor and sets a bearing for China Harbor, 9.5 miles to the northwest. I note our cruising speed of 7 knots and realize we will reach the start location somewhat later than expected. We will have nautical twilight around 5:40am, and I think Dave intends to splash around 6:00.

Dave before the start. China Harbor in background.

[0610] We arrive at China Harbor. Capt. Mark parks a couple hundred meters offshore, and Dave begins his final preparations. There is a fortuitous gap in the kelp, just as Dave and I had seen a couple weeks prior during our recon mission. Now a few minutes before sunrise, it promises to be a perfectly beautiful, placid morning.

Dave with crew chief (Davis Best), deckhand (Bill Skok), and observer (Evan Morrison).

[0620] Dave leaps off the swim step into the ocean, which measures 59 degrees Fahrenheit (calibrated among three separate thermometers). We are surprised it is even this cold, given the generationally warm water temps in other parts of California at this time. Dave swims into the cove alongside his paddleboarder, Chip. He clears the water beyond the high tide line.

Dave getting ready to jump off the boat.

[0627] Dave re-enters the water and the swim begins. Air temp 62, water temp 59, wind negligible, water glassy with small ripples.

[0630] Dave reaches Bonnie idling offshore. He wants to swim off starboard, with Chip (paddleboard) between himself and the boat. We are aiming for the gap in the kelp.

Dave and Chip, a few minutes after the start.

[0705] 66 strokes per minute (SPM). We are now past the kelp. Capt. sets bearing for Spooner’s Cove. Some small swells (< 3 ft) from the NW, as we move beyond the lee of Pt Estero. Still glassy water with ripples. I notice a jelly hovering below the surface, between the boat and Dave.

[0712] First feed - Perpetuem + Gu. Dave is getting blinded by the sunrise so he wants to swim closer to the boat to block it.

Sunrise over Cayucos.

[0727] 1 hr elapsed. 2.1 statute miles forward progress; 12.3 sm remaining.

[0745] DVM says water feels warmer. Thermometer does not confirm this.

[0752] 66 SPM, 59F sea, 67F air, NW rolling swells 3-4 ft.

[0755] 35°25.381N, 120°58.483W. 11.4 sm to go.

[0757] 3 fig newtons washed down with Perpetuem. 90 sec. feed including pee. 11.3 sm to go.

[0827] 2 hrs elapsed. Some bigger swells rolling through, occasionally 4-6 ft. No wind. We pass a boat pulling crab pots off port side. 67 SPM. 35°24.484N, 120°58.117W. 10.3 sm to go.

[0842] Perpetuem feed. DVM asks for water temp & stroke rate. Glassy water with swells.

[0857] 35°23.719N, 120°57.617W. 9.3 sm to go.

[0900-05] Visited by some porpoises. DVM pauses briefly to pee.

[0927] 3 hrs elapsed. Kyle replaces Chip on paddleboard. Humpback whale spout & breach off starboard. 67 SPM, 59F sea. 35°23.034N, 120°57.296W. 8.47 sm to go.

Dave and Kyle.

[0957] Perpetuem feed. DVM asks for distance covered on next feed. Wind < 5 kts, ripples on water. 35°22.405N, 120°56.845W. 7.65 sm to go.

[1015] 2 seals nearby, playing.

[1027] 4 hrs elapsed. Perpetuem + fig newtons. DVM pleased with progress report. 67 SPM, 68F air. 6.85 sm to go (over halfway).

Morro Rock, 4 miles off port-side.

[1045] Another humpback spout & breach.

[1057] Perpetuem + Gu. Wind 5 kts, a bit more texture on the water now. 35°21.211N, 120°56.025W. 6 sm to go.

[1104] DVM asks for Clif shot blocks on next feed.

[1127] 5 hrs elapsed. Perpetuem + Clif shot blocks. Seeing some whitecaps off starboard (to the west). 35°20.386N, 120°55.662W. 5.1 sm to go.

[1140] A bit choppier now. Whitecaps close but not on us yet. 64 SPM.

[1157] Perpetuem + Gu. DVM annoyed at chop. Wind 7-10 kts, scattered whitecaps. 35°19.659N, 120°55.529W. 4.33 sm to go.

[1227] 6 hrs elapsed. Perpetuem feed. Chip replaces Kyle on paddleboard. 66 SPM, 66F air. 3.6 sm to go.

Dave and Kyle in afternoon conditions.

[1240] Friends of DVM Peter Steynberg (kayak) and Paul Teixeira (SUP) approach from the south, presumably having launched from Spooner’s Cove.

Some kayakers and a SUP joined us near the end.

[1257] Perpetuem + Gu. Wind has died down a bit - ~5 kts. 35°18.474N, 120°55.060W. 2.9 sm to go.

[1327] 7 hrs elapsed. Perpetuem feed. Less wind, water smoothing out. Sailboat crosses in front of us, at speed. 65 SPM. 35°17.811N, 120°54.678W. 2.1 sm to go.

[1340] Two more kayakers - Greg Boege and Mike Nunno - join us, forming an “armada” to accompany Dave into Spooner’s Cove.

[1357] 1.3 to go. Perpetuem + Gu feed. Spooner’s Cove is clearly visible. 70F air and sunny.

Friends and supporters await Dave’s finish at Spooner’s Cove.

[1427] 8 hrs elapsed. Last feed. Kyle & Adam (Dave’s sons) enter water to buddy-swim.

Dave’s sons Adam and Kyle swim into the beach with him.

[1445] Dave clears the water @ Spooner’s Cove. 8 hr 18 min 24 sec elapsed. Crowd gathered on beach cheers.

Dave greets his wife.

Dave gives an interview with the local media. Photo by Rob Dumouchel.

I observed this swim from start to finish, and affirm that it was conducted in strict accordance with the Rules and Spirit of Marathon Swimming.

Evan Morrison
Marathon Swimmers Federation

Original Logs

log 1 log 2 log 3 log 4

Swimmer Narrative Report

Crossing of Estero Bay in San Luis Obispo County in California

The Estero Bay swim is behind me, and it was a great experience. This was a shorter swim (14.4 miles), in coldish (60-61 degrees F) water. I had a lot of Angst leading up to the swim. I perceived the waters of Estero Bay to have an extra dose of loneliness and remoteness than my previous swims, and I perceived the waters were filled with more wildlife than I’m accustomed to. Local surfers consider some of these waters to be “sketchy”. But, there is Risk and there is Perception of Risk, and those two things are often wildly out of synch with each other.

The route, largely north to south, is shown here:

swim route

The swim start, on the north end of Estero Bay, was at a natural cove called China Harbor. China Harbor is on private lands north of Cayucos, and Evan Morrison and I scouted out the start a couple of weeks before the swim date. We got permission from local landowners to cross their land, and we gave a heads up to the rural sheriff deputy that we’d be hiking through this area. (Landowners and sheriffs have been monitoring this area because a couple of times over the last two years, panga boats loaded with bales of marijuana have landed along this remote shoreline, so there is a strong sense of “neighborhood watch”.)

Evan and I hiked in, and looked down from the bluffs onto the planned swim start—a much protected cove. It was about 300 meters across, and appeared to be a beach filled with cobblestones; a natural place for the swim start, although I was concerned about the rocky beach. The coastline here had tremendous amounts of kelp growing along it, but there was a wide and fortuitous kelp-free zone that was about 80 meters across and would provide an easy and open departure from China Harbor.

china harbor sat

I had located an escort boat, the Bonnie Marietta, owned and operated by Mark Tognazzini of Morro Bay. Mark proved to be the right man for the job. He has decades of experience in the local waters, and he had great traits that we all look for in swim escorts: he was confident, competent, affable, no-nonsense, and he became vested in having the swim being successful. What more could a swimmer ask for? Here are Mark and I a few weeks before the swim.

capt mark

Mark’s boat, the Bonnie Marietta, was very appropriate for the task at hand; she is a 38’ commercial boat, and Mark has owned her for at least a couple of decades. Also, she is emblazoned with a very sexy mermaid.

bonnie marietta


The swim was largely uneventful; there was no drama that I was aware of (that’s how I like it), and I was well-trained. My support crew has been with me on previous swims, and everyone knows what is expected of them. We had a well-articulated plan, so our execution of the swim was really just a pre-ordained march. (Which is to say that we’d controlled the variables that could be controlled, and that then we surrendered ourselves to the variables outside of our control.)

We motored out (8 miles) from Morro Bay at about 5:45 am. We idled about a hundred yards from the shore, and my paddle boarder deployed and then I jumped in shortly thereafter. The water was 59 degrees at the start of the swim. I swam in to the cove, and was pleasantly surprised by a wide swath of sand allowing my exit and re-entry without encountering the cobblestones that I’d expected. So then it was a matter of getting to dry sand, turning around, and entering the ocean. That sandy beach seemed like a good omen. I settled into my swim within fifteen minutes, and my head stayed in a good place for the duration of the swim.

The boat headed south, with my paddle boarder off of the starboard side, and then myself furthest out. I was very comfortable with this arrangement, because although I am an alternate breather, I’m most comfortable breathing to my left. This allowed me to breathe towards the shore, away from the (minimal) wind chop and swell, which mostly quartered me from the northwest.

There was an extra sweetness to this swim. Both my boys (Kyle, 24; Adam, 21) were along. Shortly after my last swim (July 2013, a 20.3 mile swim in a Swedish lake), Kyle became suddenly ill with a neurologic disorder called Guillain-Barré Syndrome (GBS). He was near death….intubated for a month; paralyzed from the neck down; four months in hospitals and then five at our home; he became a 130 pound wraith. But he weathered the acute phase of the disease, and is still recovering from the illness, but he is strong and healthy again, and he paddled next to me for 3 hours on this swim. And at the end both he and Adam swam in with me.

There was another aspect of this swim to note.

The swim was the brainchild of Evan Morrison: Evan conceived of it; Evan was first to articulate it. He was to swim it, and I’d observe him. During my seeking of support boats for Evan’s swim, I became interested in the swim also. We made arrangements that Evan would swim on a Friday with me observing. Then on Sunday I would swim with Evan as my observer. This was what was meant to be—in one weekend Evan would have this First to Cross, and I would have the Oldest to Cross. But it did not turn out like that. The winds kicked up on Wednesday through Friday, culminating in small craft advisories. The boat captain indicated that it was ill-advised to attempt a crossing on Friday, and we concurred with him. But this meant that Evan did not swim, and so I became the first to cross Estero Bay. I have great ambivalence about this.

spooners sat

This was my first marathon swim in my home turf. About four miles from shore, we were joined by some friends (one on a kayak and one on an SUP). Then a couple miles out two more kayakers joined us. I felt that we were becoming invincible, an armada whose only option was success. My boys, my healthy boys, swam to shore with me. As I got my feet under me on the sand of Spooner’s Cove, the profound relief and satisfaction washed over me. Lisa (my wife) was on shore. A variety of local friends showed up to celebrate the crossing.

A great day in Estero Bay.…the ocean was good to me, to us. On this day my crew and I moved across the water, together.

A Closing Thought

This swim was observed by Evan Morrison, and was swum according to the rules articulated by the Marathon Swimmers Federation. The MSF has created a much-needed set of swim rules that provide a means for authentication of swims performed in bodies of water that have no governing organization. MSF provides rules and swim documentation guidelines, such that if an observer provides appropriate evidence of an observed swim, then that swim can be impartially scrutinized, verified, and ratified. Thus the swim can be authenticated and recognized by the marathon swim community as a valid performance in bodies of water with no local governing body.

For instance, two years ago I swam a 20.3 mile traditional marathon swim in an unknown (to marathon swimmers) lake in Sweden called Lake Siljan. I had a Swedish crew chief who also acted as my observer. He gathered much evidence during the swim that, once organized and submitted, may potentially be authenticated by MSF, resulting in my efforts being a recognized and valid swim, according to the MSF definition of a marathon swim. What an excellent mechanism this is, so that swims around the planet can be authenticated and recognized!

These rules and documentation guidelines also perform another important task. There are some people in the global swim community that make claims of having completed marathon swims, yet there is no clear evidence to back up these claims. However, now anyone interested in performing a swim outside of the existing governing organizations has a means to document their swim beyond reasonable doubt. And if a person chooses to swim a body of water, yet does not avail themselves of this means of documentation, then the onus is on them–they are remiss in not taking the necessary steps to receive recognition for their efforts.

So, I applaud the efforts of the MSF in moving our community towards the “golden rules” of marathon swimming (transparency of swim conduct, and independent observation). It will be much easier to dispense of potentially false claims by a small subset of our global swim community, and off-the-grid swims can now be adequately authenticated and recognized.


Supporting Data

Marine Weather - NOAA Buoys

There are no buoy stations in Estero Bay proper. The nearest ones include Station 46215, Diablo Canyon, ~5 miles southeast of Point Buchon, and Station 46028, Cape San Martin, 53 miles northwest of Point Estero. However, the relevance of these data is limited: the Diablo Canyon buoy’s sea temperature readings are affected by the adjacent nuclear facility, and the Cape San Martin buoy was non-operational on the day of the swim.

The nearest operational buoy with reliable data is Station 46011, Santa Maria, 22 miles southwest of Point Buchon. This buoy provides the following readings for August 16:

Time (GMT) Wind Speed (m/s) Wave Height (m) Air Temp Sea Temp
13:50 5.5 1.6 17.3 17.2
14:50 3.8 1.55 17.3 17.3
15:50 4.2 1.52 17.4 17.3
16:50 4.5 1.52 17.5 17.4
17:50 5.3 1.43 17.6 17.5
18:50 4.2 1.49 17.7 17.6
19:50 5.2 1.58 17.9 17.7
20:50 5.8 1.66 18 17.9
21:50 5.3 1.85 18 17.9


Location: Morro Bay, California

2015-08-15 Sat 11:42 PM PDT    4.2 feet  High Tide
2015-08-16 Sun  6:23 AM PDT   Sunrise
2015-08-16 Sun  6:51 AM PDT    0.4 feet  Low Tide
2015-08-16 Sun 12:54 PM PDT    3.5 feet  High Tide
2015-08-16 Sun  6:46 PM PDT    1.6 feet  Low Tide

Source data

Media Coverage