The Power of a Surge

[Alaskan Sea-Duction]

Last week I experienced something I have never before experienced. The ocean surge.

The entrance to Mazatlan Harbor is one such place. The entrance is very narrow and as a swell enters the entrance, half of the swell crashes on the rocks and the other half flows into the harbor.

Pairadice is tied to Marina El Sid, the surge affects this marina. As a swell enters the marina it pushes the water into the marina and moves all the boats back. As the swell moves back to sea, the water switches direction and moves out.

So the timing to enter the entrance is critical. A 45-60 ft sail boat mis-judged. As he entered the harbor, a swell caught him, causing the boat to "surf" the swell. This cause him to lose steering. He did not have enough power to back off and he crashed into the rocks snapping the mast off with the keel broke off. He was able to get off the boat before it rolled.

Took a crew with barrels to float it enough to get it to a dock.They worked for a couple of days and were able roll the SV upright.

I thought the currents of the PNW was bad.

 

[Wayfarer]

Jaysus. That's a bad day.

 

[OldDan1943]

Jaysus. That's a bad day.

Local knowledge???

 

[Alaskan Sea-Duction]

Local knowledge???

Yes if they would answer the VHF, which the locals do not.

 

[MurrayM]

Have never used or even seen a Seabrake, but this scenario (broaching uncontrollably while surfing a wave) is exactly why they were invented:

https://www.sail-world.com/Australia/Seabrakes-a-must-have-for-offshore-sailors/-22274?source=google

 

[DDW]

Wonder what kind of boat? Tangles with rocks are not predictable, but the keel breaking off should never happen on a well built sailboat, without complete destruction of the hull. It is happening more in the last 20 years as boats have become less well built.

 

[MurrayM]

Wonder what kind of boat? Tangles with rocks are not predictable, but the keel breaking off should never happen on a well built sailboat, without complete destruction of the hull. It is happening more in the last 20 years as boats have become less well built.

If they broached at surfing speed and hit a rock...that would pack a serious wallop!

 

[OldDan1943]

I had one for my N46. 2 big bags. One for the rigging, the 2nd for the brake itself. I had the space to stow it on the N46. Never used it. Donated it to Chapman's school. The really appreciated the donation.

 

[OldDan1943]

Yes if they would answer the VHF, which the locals do not.

For money?

 

[MurrayM]

I had one for my N46. 2 big bags. One for the rigging, the 2nd for the brake itself. I had the space to stow it on the N46. Never used it. Donated it to Chapman's school. The really appreciated the donation.

Was it a Seabrake, or a parachute anchor? Two entirely different beasts!

 

[OldDan1943]

Was it a Seabrake, or a parachute anchor? Two entirely different beasts!

brake, as mentioned in my answer.

In desperation, anything of size will assist. Not as great as an official brake. Of course if the real brake hangs up on the rocks, be prepared to cut it loose.

 

[MurrayM]

brake, as mentioned in my answer.

Must have been a big one.

If I was to be crossing bars, think I'd find the room. (Runs at about 7' depth while boat is under power, so unlikely to hang up on rocks).

 

[OldDan1943]

Must have been a big one.

If I was to be crossing bars, think I'd find the room. (Runs at about 7' depth while boat is under power, so unlikely to hang up on rocks).

Oh yea, 2 BIG bags. The right size for the N46. If I tried to rig it on my 34ft, I think it would pull the cleats out. LOL
I'm not sure which is more trouble, deploying it or retrieving it.

 

[MurrayM]

Oh yea, 2 BIG bags. The right size for the N46. If I tried to rig it on my 34ft, I think it would pull the cleats out. LOL
I'm not sure which is more trouble, deploying it or retrieving it.

A third option is possibly experiencing what the sailboat did

 

[Alaskan Sea-Duction]

Have never used or even seen a Seabrake, but this scenario (broaching uncontrollably while surfing a wave) is exactly why they were invented:

https://www.sail-world.com/Australia/Seabrakes-a-must-have-for-offshore-sailors/-22274?source=google

Not for the small skinny entrance.....

 

[Alaskan Sea-Duction]

Wonder what kind of boat?

Crusty may know. I had the impression it was a good boat.

 

[SteveK]

I had a sailboat and one thing on check list annually was the bolts that held the keel on. Check for corrosion or softness around them.What I saw was bolts with nuts over washers sufficient to hold the keel to the hull, BUT on reflection a hard hit could easily rip them through the glass bottom without I expect half the hull taken with it.

 

[Alaskan Sea-Duction]

I had a sailboat and one thing on check list annually was the bolts that held the keel on. Check for corrosion or softness around them.What I saw was bolts with nuts over washers sufficient to hold the keel to the hull, BUT on reflection a hard hit could easily rip them through the glass bottom without I expect half the hull taken with it.

When you look at the hull, its nice and clean. We guessed the SV was just put in the water from the hard. It hit hard.

 

[DDW]

I had a sailboat and one thing on check list annually was the bolts that held the keel on. Check for corrosion or softness around them.What I saw was bolts with nuts over washers sufficient to hold the keel to the hull, BUT on reflection a hard hit could easily rip them through the glass bottom without I expect half the hull taken with it.

Too many sailboats built these days with detachable keels. "Tear along the dotted line." The ballast keel on a sailboat is not an optional or disposable item. No clear picture of the bottom on this one, but on many like it recently, keel cleanly detaches itself from the hull without much damage. This should not happen, rocks or no rocks. If the keel leaves without tearing a substantial bit of hull with it, the engineering was substandard.

 

[REO]

I have been in and out of that harbor several times on a Mason 53. It is no fun, especially since they often run a dredge that blocks much of the entrance. The cruising guides have good information on when it is safe. I can't see how any contraption could be deployed in that skinny twisted entrance. The best strategy is to come in at slack tide. There is an easy entrance harbor a few miles south to wait. I was in a hurry once. Won't do that again.

 

[Yachtman]

For the uninitiated, how wide is this entrance? Is this surge an all day, everyday issue? Seasonal? I’m used to more of a traditional ‘inlet’ and I’ve been through some scary inlets, but this surge thing just sounds ‘sporty’!

 

[REO]

Inlet surge problem

This problem exists in a few marinas on the west coast of Mexico. It is caused by tide and wind. The marina just north of Ensenada and the entrance to El Cid and Marina Mazatlan are good examples. These marinas were built where the ocean didn't want them. In Ensenada the marina was built on a beach. A sea wall creates a basin for the docks. The entrance is narrow and perpendicular to the beach. To enter you run at the beach and make a sharp left turn when you see the opening. Very exciting when waves are breaking. Once inside, I have seen the tidal surge break dock lines when wind and tide build up together. Marina Mazatlan and El Cid were built where a shallow swamp created a large basin. The entrance was cut from a sandy beach area. Same problem. In Mazatlan they have to run a dredge constantly to keep the entrance from silting in. Tidal surge can be a problem even at the docks in El Cid. The Mexicans have not learned not to mess with mother nature. There is a "marina" somewhere north of Ensenada that was dredged and platted for a dockside community. When we visited by car they had not found a dredge strategy that could keep up with the silting.

 

[Hippocampus]

There’s been a transition in sailboat design. To maximize endplate effect and improve efficiency the keel stub being part of the canoe body has been eliminated in many recent designs. This is ok if done in conjunction with beefing up the internal grid bearing the forces and of course number, design and strength of the keel bolts. To do it “right” is expensive and even then prone to possible failure. Unfortunately given small endplate for lateral forces to work on failures have occurred. Not only fractured keel bolts but also laminate torn away as occurred with the mega yacht Oyster off the coast of Spain. The keel bolts didn’t fail but rather the surrounding structure.
This design element also leaves the vessel prone to unseen and potentially future catastrophic failures down the road if even minor groundings occur. When the front edge of the keel is struck the trailing portion of the keel is forced upwards into the canoe body. This causes crush. The fractures of the laminate fibers and supporting grid may not be visually apparent. The structure may suddenly fail as it works in a seaway or even more moderate loading.
We intentionally had an Outbound built for us as there have been zero keel failures inspite of a long history of heavy service including coastal and open ocean passages. Inspite of being a fairly high aspect bulbed fin they are internally ballasted and seriously overbuilt. A expensive detail but provides a long safe service life. Cost of a boat is cost to buy minus return when you sell it. We are actively looking to buy a blue water trawler. Similar levels of construction in series production vessels is quite limited. This time it will be new to me rather than new. But the same formula holds. Expensive in but higher return when swallowing the anchor.
Still you need to be prudent. The MFD isn’t enough. Cruising guides remain helpful. Rages, surges and bars aren’t to be trifled with. There are many scary places. The Bahamas, leewards, Windwards, coast of Portugal, bay of biscay. The list is extensive not just the west coast of Mexico or US where timing is everything. You must expect to have to be entirely self sufficient. Sure you may luck out and a friendly fish boat will talk you in as you follow them but that nothing to count on. As they say “ it’s not the ocean that commonly sinks you...... it’s the hard edges”.

 

[Alaskan Sea-Duction]

For the uninitiated, how wide is this entrance? Is this surge an all day, everyday issue? Seasonal? I’m used to more of a traditional ‘inlet’ and I’ve been through some scary inlets, but this surge thing just sounds ‘sporty’!

This problem exists in a few marinas on the west coast of Mexico. It is caused by tide and wind. The marina just north of Ensenada and the entrance to El Cid and Marina Mazatlan are good examples. These marinas were built where the ocean didn't want them. In Ensenada the marina was built on a beach. A sea wall creates a basin for the docks. The entrance is narrow and perpendicular to the beach. To enter you run at the beach and make a sharp left turn when you see the opening. Very exciting when waves are breaking. Once inside, I have seen the tidal surge break dock lines when wind and tide build up together. Marina Mazatlan and El Cid were built where a shallow swamp created a large basin. The entrance was cut from a sandy beach area. Same problem. In Mazatlan they have to run a dredge constantly to keep the entrance from silting in. Tidal surge can be a problem even at the docks in El Cid. The Mexicans have not learned not to mess with mother nature. There is a "marina" somewhere north of Ensenada that was dredged and platted for a dockside community. When we visited by car they had not found a dredge strategy that could keep up with the silting.

Reo, good and true points. The entrance is very narrow, which doesn't help. I know know why the party boats are full throttle when going through the entrance. Dock A gets the worst of the surge. Your boat goed back and forth 24/7!! Rocks you to sleep.

 

[Crusty Chief]

Attached is a google earth pic and a pic of the entrance from Navionics.

This is a very narrow entrance, about 70 feet across at the narrow point, and usally a dredge is in this vicinity. Local knowledge is one thing as most of the tour boats that traverse the inlet have enough power and speed to handle almost any issue when entering or exiting.
The sailboat that ran aground was caused by several things. The dredge was in the channel at the time and the sailboat(drawing 7.5 ft) entered at high tide. It is recommended to enter slack to high depending on how much you draw. When you enter the channel you pretty much have to commit to entering blind as you wont see exiting boats or the dredge if he is active in the channel. Now have swell on your stern pushing you in and it can get pretty dicey, I have experianced this, NO FUN!

We have experienced surge in several places on the west coast. The San Francisco Bay marina’s downtown where very noticeable and this may have been our first experience, main reason we choose Sausalito to stay.

Anyway El CID is a nice facility other than the Surge. For future reference, the dredge normally works the entrance Monday-Friday from about 9 AM to 4 PM. He will move the dredge to the rock wall when a few boats stack up in either direction, they dont have any warning system in place and don’t communicate via the radio. But the locals may have a secret channel that they talk on, we just never found it.

Hope that explained it a bit better

Cheers

 

[OldDan1943]

If you search Youtube, you will see videos of the Haulover cut in FL.
Based upon the videos one would believe Haulover is the worse cut on the southeast coast of FL.
Yes, it has a delta so you'd be advised to stay close the outer edge, watching your depth sounder and avoiding the rocks.
When I am outbound, I go passed the cut, watching for incoming traffic. I circle back around and staying reasonable close to the outside edge and exit.

I hear the same warning about the Stuart FL. But it is a nice wide cut compared to Haulover. In Stuart you learn to stay on the back side of the waves cautiously, careful not to broach or climb over the top of the wave.

I did the Stuart and Haulover cuts in my speedy 8knt N46 and my SD AT34 that is supposed to go a roaring 15knts.
So far, common sense has been my savior. If need be, stay outside watching the waves for a bit and then choose the next wave to ride.

There will always be idiots who believe, they must go max speed to get in or out of a cut and then, they wonder why they bury their bow as they climb up and over the top of a wave.
I am very surprised the bottom of the Haulover cut is not littered with sunken bow riders. That open fwd cockpit, in my feeble mind, is inviting disaster.

I have also seen people who believe, as soon as they clear the cut, they can put their beam to the waves. WRONG!!! Go out a distance beyond the breaking and big waves and then quarter the seas.