Hola Amigos,

Yes, the crew of Ahwahnee is alive and well and still in Huatulco. We have finished those boat projects necessary for us to leave. However, we still need to do our Zarpe and have Mexican Customs and Immigration visit the boat before we can officially depart from Mexico. After that we wait for a weather window to allow us to cross the Gulf of Tehuantepec without getting hammered by the gale force or greater winds and associated steep wave conditions common in this area.

Currently, we are awaiting for our friends on Joyeux (Rob and Sue) to arrive before we start this final checkout procedure. Meanwhile, we continue to work on the ever present boat project list. Once our friends arrive, all of the officialdom is satisfied, and the weather looks good its off to Bahia del Sol, El Salvador to attend the first-ever El Salvador Rally.

So let us fill you in on the earthquake generated tsunami experienced in Marina Chahue, the Santa Cruz darsena, and the Bahias de Huatulco on February 27 as a result of the 8.8 earthquake that occurred at about 0300 in the morning centered approximately 55 miles off the coast of Chile at depth of about 18 miles. To put this in perspective the recent Haitian earthquake measured 7.0.

Submarine earthquakes can initiate tsunami waves as a result of the instantaneous displacement of sea water with the tremendous release of energy along the fault line. The resulting tsunami wave radiates around and away from the point of origin impacting any coastal land mass in its path. One such coastal area down range from the Chilean earthquake is the southerly facing Mexican coast on the north side of the Gulf of Tehuantepec (i.e., Bahias de Huatulco, etc.). The crew of Ahwahnee first became aware of the potential tsunami when our friend Jean from S/V Mita Kuuluu came by about 0830 with the news of the earthquake. At that time we thought the tsunami wave would arrive in our area about 0900 at a height of about 3.0 feet. Kathy and I left the boat and walked up to the walkway above the sea wall with camera in hand. We planned to wait there for what we thought would be a slight surge of water into the marina after traveling nearly 3000 miles from its origin. At a little after 0900 we took some pictures of some evidence of surge in and out of the marina accompanied by a lot of fish activity on the water surface. We thought we had captured the event and went back to the boat by about 0930. We didn't realize the show was yet to come.

As we walked back to the boat we noticed that Swan Fun (Danny and Kathy) at the head walk end of our dock was gone from its slip. We thought they were just out for a day of sailing and testing things out prior to their anticipated departure for Puerto Vallarta. The real story is that they were having an adventure getting away from the fuel dock in the darsena in Santa Cruz as the initial tsunami wave entered the bay. For the rest of Swan Fun's story in Kathy's own words go to Google and type in Tsunami in Huatulco. After leaving Santa Cruz in chaos, Swan Fun returned to their slip in the relative calm of Marina Chahue and went to their home overlooking the darsena to watch the action. Shortly after Swan Fun escaped the darsena and returned to Marina Chahue John (Pelican) reported that the darsena was the scene of many fishing and tour boats (pangas) washed up on the walkway above the sea wall or capsized in the moorage which included the Port Captain's boat. Surge from the tsunami reached some of the tourist shops. At that point Kathy (Ahwahnee) and Jean (Mita Kuuluu) decided to take a taxi to Santa Cruz and see things up close.

Beyond general interest, tsunami conditions in Marina Chahue were not nearly as dramatic as the happenings in Santa Cruz. The initial surge described by friends Cheryl and Eric on S/V Sarana was a small wave traveling into the canal adjacent to the marina. At the same time the flow through the narrow cut was generating white water at the marina entrance. The ebb and flow of the tsunami surge continued for about the next 60 to 90 minutes before finally subsiding to the surge of the normal on shore wave action. Those boats able to escape the darsena moved into Marina Chahue filling every available space.

At the maximum the surge height in Marina Chahue reached about 4 feet 8 inches as measured by Eric of Sarana. The floating moorage rose to a point where the top of the pilings was about chest high. Normally its a couple of feet above my head except during extreme high tide events. During the ebb of the tsunami wave, the outside red navigation buoy was being sucked under the water surface in the extreme flow velocity generated as the water from the marina passed through the narrow entrance. After all of the excitement, it was evident that the boats in Marina Chahue escaped the fate of many in the darsena at Santa Cruz because the height of the tsunami surge was limited by the canal adjacent to the marina, and the storm runoff canals at the back of the marina, and outside the marina entrance acting as safety valves as the water level rose in the confines of the marina. Boats in Marina Chahue did not sustain any damage.

The really good news is that except for minor property damage from localized flooding impacting shops in the darsena and boats washed ashore, swamped or capsized we haven't heard any reports of lives lost or serious injuries sustained.

Earthquake and tsunami info:
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The Richter Scale is not linear. The increase in strength between a 7.0 and 8.0 is a factor of 32 times. To get from 8.0 to 9.0 is another factor of 32. These are not added to compute the strength of 9.0 over a 7.0, but are multiplied. This means that the strength of a 9.0 quake is over 1000 times greater than a 7.0. Therefore, the 8.8 Chilean Earthquake was on the order of around 800 times more powerful than Haiti's devastating 7.0 quake.

Lacking the exact names of the plates involved, let me use the South American Plate (SAP) and Submarine Plate (SMP) to provide a brief description of what might have initiated the tsunami wave when the earthquake occurred. Visualize the SAP as the end of a spring board where it contacts the SMP in the subduction zone off the west coast of Chile. As the SMP is forcing its way under the SAP, the end of the spring board is being pulled down and deformed under the extreme pressure. The force exerted on the SAP continues to increase over an extended period of time (maybe since the 9.5 quake in the same vicinity that generated the tsunami wave that devastated Hilo, Hawaii in 1960). At any rate the forces build until there is a structural failure in the overriding plate and the SAP spring board suddenly rebounds displacing an enormous volume of sea water as it kicks upward. The action set in motion a tsunami wave that will ultimately travel around the globe and impact coastal areas in its path.

The degree of impact from the tsunami is largely dependent on the distance from the point of origin, the orientation to the approaching wave, and the depth and geometry of the impacted coastal area. In the case of Marina Chahue and the Santa Cruz darsena it is evident that the primary difference in impact was the presence of the canals around the marina which limited the surge height and didn't allow water to overflow the top of the surrounding sea wall. In the darsena the surge forced water over the top of the sea wall resulting in a surge height possibly 3 or 4 feet higher than that experienced about one mile east in Marina Chahue.

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Yahoo our new dinghy is here! About 9:30 a.m. on February 12th we had a knock on the boat and were informed there was a package at the office. Tom grabbed his hand truck and off he went. Should have seen the smile on his face as he brought it back to the boat. Not sure if it was one of relief or excitement - maybe both.

But, you need the rest of the story. Must say that UPS did deliver. We were a bit concerned as we checked the tracking a couple of times a day and once it got to Mexico City (within two days of ordering), it seemed to sit and we weren't sure by the remarks what needed to happen next. Finally, when the first posted delivery date of February 3 came and went, I placed a call via Skype to UPS Mexico. I somehow heard select "9" in Spanish and did get connected to a woman that spoke as much English as I speak Spanish. After several frustrating attempts, she put a supervisor online and he took my e-mail and gave me back to the woman. As luck would have it, the office secretary here happened to walk by and I enlisted her assistance in understanding what I needed to do. After the phone call I gathered I needed to write UPS about the value and non-commercial use. She had written down the e-mail and my fingers were typing. I was so confident the issue was resolved. But, the secretary doesn't speak English and so we had a breakdown. She had written down the wrong e-mail address and I didn't know about "the" forms.

Next day I had an e-mail from the supervisor in Mexico City. He had attached all the forms (in Spanish) that needed to be completed, signed and e-mailed back. I printed them, went to see our neighbors who speak and read Spanish and within an hour had them filled out in Spanish. Tom signed them, we scanned and sent them back. Now we were back into the tracking loop and every few hours looking to see if anything had happened. Two days later, we had an e-mail indicating what we needed to pay at Banamex. You should have seen us change quickly into our "go to town" clothes, grab our pesos, hail a taxi and we were off. We splurged for a taxi back to the boat, scanned the receipt and e-mailed our now best friend in Mexico City. He immediately e-mailed back that the package would be released that day.

So within three days we got the knock on the hull and the day of assembly began. A week has now gone by and we've had an in the water test, refit the old dinghy chaps onto the new dinghy with many many alterations, completed strapping to put the dinghy on the davits and Sunday will be putting on the outboard and going for a spin in the bay.

As to the whereabouts of the old dinghy. It is finding a home via the missionaries on our dock. Tom dug out all the accessories, new repair kits and away it went. We'll probably see it go by looking like new going out fishing.

So we can put a check mark by that project and move on. Maybe we will get out of Huatulco soon.

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Using the UPS tracking system, we saw online this morning that our dinghy made it to Mexico City yesterday. Date of delivery is February 3. Feel like we should be taking bets on delivery time and amount that will be due. Anxious and excited in Huatulco.

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