By Jan Chaiken and Marcia Chaiken
Can you imagine that at one time Rio Chahué flowed vigorously and majestically down from the mountains north of Crucecita to Chahué Beach and from there to the Pacific Ocean? Although now there is a bridge labelled “Rio Chahue” on the highway from the airport to Salina Cruz, at this season of the year the bridge crosses over a dry river bed. South of the highway, and all the way through town, the river bed is now a mundane concrete channel, dividing roads such as Tamiagua and Guelaguetza into two one-way corridors on either side of the concrete watercourse. The channelled Rio Chahué passes by the Marina Park Plaza Condo Hotel and then flows under a handsome bridge where it reaches its ignominious end at a dam.
Beyond the dam is Marina Chahué, visible from the road connecting Santa Cruz and Tangolunda. The marina has berths for various sizes of pleasure boats and the shore is lined with restaurants, an area for repairing and storing boats, offices of the marina, and a fueling station. The marina was constructed by Fonatur, the governmental agency that creates and maintains a number of tourist destinations in Mexico including Ixtapa, Cancun and of course, Huatulco. Rather than providing better services for the local fishermen who had long lived in the area, Fonatur’s explicit purpose was to attract foreign visitors and extremely wealthy Mexicans on their super yachts.
Not only were the piers, buildings, and infrastructure such as sanitation, electricity, and potable water built there by Fonatur, but the entire waterway, the channel that allows boats to enter the marina, and the breakwater which separates the marina from the rest of the bay and provides the boats protection from rough seas. An extensive dredging operation removed tons of sand to increase the depth of the area allowing safe access by boats and avoiding boats running aground with the possibility of releasing contaminants such as fuel into the bay and the ocean. The original dredging plans also envisioned that dredging would need to be repeated every three years.
This year, those of us who live where we can look out over Chahué Bay were treated to a daily sight of an oddly-shaped blue tugboat dragging a barge out toward the horizon and the ocean beyond. Depending on the wind direction, the barge might have been to the left or right of the tugboat, or behind. Trying to guess the route and destination of the tugboat was a good idle-time preoccupation, as a round trip of the paired tugboat and barge took more than an hour. This routine has been repeated several times a day for months now, and may still be continuing as this issue of The Eye goes to press.
In the marina was a blue dredge, sporting a crane-like structure with a scoop hanging from it. The scoop is like a clam shell or two hands that come together with the fingers intertwined. In Spanish it is called a cuchara bivalva or bivalve spoon. It lifts stuff from the floor of the marina and deposits it in the barge that then gets tugged out to sea. The dredge has been working methodically from the base of the dam out to the bay and then back, clearing out the entire floor of the marina.
We interviewed the Fonatur employee who is in charge of the dredging operation, including contracting for the dredging services, reviewing progress, and paying for the work, Arq. Omar Sánchez, to find out just how disgusting might be the sludge that gets lifted out of the floor of the marina. He informed us that it is not sludge at all, but very fine, clean sand that gets pushed into the marina gradually, over the years, by the action of waves, especially during storms. He proudly told us that the material lifted by the dredge scoop is subjected to laboratory analysis and does not pose any harm to the environment. To make his point, he encouraged us to consider that fish live happily in the marina before, during, and after the dredging operation and can be seen leaping over the surface of the water. (Actually, he didn’t say “happily.”) Small quantities of sludge do make it over the dam from Rio Chahué into the marina, but they are not significant for the dredging operation.
He said the dredging is needed because the bottom of the marina gradually rises high enough that the typical boats that visit may not be able to reach their assigned docking position or the fueling station. In addition, without dredging, the largest yachts (up to 75 feet long can be accommodated) would be too deep to reach the marina.
We also asked why a mechanical dredge is used, with its tediously slow operations that have stretched out over months. Another type of dredge, which works by hydraulic suction, would be substantially faster and more efficient. He said that a suction type of dredge has too deep a draft (distance from water line to keel) and could not itself get into the marina to carry out the dredging. Residents who live on boats in the marina told us that the last dredging operation, five years ago, did use a suction dredge. It so forcefully discharged the watery material from the marina that you can still see the area directly to the west of the marina looks like a wasteland with no large vegetation remaining.
One question we and other The Eye writers had was where the tugboat goes with the barge to dump the dredged material. Sr. Sánchez said that the barge is taken out to a place where the depth of water is at least 400m. The contents of the barge are then released to fall into the ocean. The tugboat never goes to the same location twice, which is why we shore-bound observers could not deduce any pattern to the tug’s round trips.
We inquired who employs and supervises the dredge workers. Although Sr. Sánchez said he was not authorized to release that information, we were told by a security guard at the marina that the Mexican Navy operates and supervises the dredging operation. We did not have official verification of naval oversight but we did see a man looking like a naval officer arrive in a military truck labeled Marina, and from there he went in a motorboat to talk to the workers on the dredge.
Fonatur has consciously tamed Rio Chahué to the point of extinction and provided marina shelter for people who live on boats or visit our area. But we’re quite sure they did not intend to have a dredging project that would provide such interested scrutiny by tourists and residents.