September 06, 2002
Canter - Dam size, location?

Ron Canter has tried to get some information on the location, size, and impact of the proposed dam. Here's Ron:

The emails are flying thick and fast so I thought I'd toss one in.

As best I can tell from maps, a dam in the Boca del Cerro gap would be in Tabasco at the east end and Chiapas (barely) at the west end. Since the mountains end here, it is the last practical dam site. In the coastal plain downstream there are no hills to put a dam between. Any dam at Boca del Cerro will flood far into Chiapas, both upstream and up side valleys to the west. They would have to get Chiapas's OK to build. (MORE below)

I've tried to get some better figures on a possible dam but there's
not much to get. Conagua's website http://www.cna.gob.mx is extensive,
but doesn't have any real data on anything. It goes on about
conceptualizations and action plans, but the only thing of interest was a
link to "Agua Para las Americas en el Siglo"
http://sgp.cna.gob.mx/financiamiento/evento_2002/index_aa2.htm . This
"Water for the Americas in XXI Cen" forum will be in Mexico City Oct 8
through 11. Might be someone with answers at it, but its $2000 pesos a
head.
The CFE website http://www.cfe.gob.mx has a section on future
projects, which includes a map showing three hydros in Chiapas and one
combined cycle plant in Tabasco. Unfortunately the map is very
generalized, with little tailfin symbols for hydros only roughly located.
The one most likely to be Boca del Cerro is slated to be finished by 2011,
a time frame that allows working out any differences with Chiapas over
taxes. Its capacity is to be 3,978 Mw, of a total 28,862 Mw increase
planned for all of Mexico. In other words CFE hopes that the Usu' will
supply 1/7 of all the increase in electric generation for Mexico in the
next 10 years. CFE and Conagua may not give up right away on this.
Comparing Hector Perez Ruiz's figure for area drowned, 302 mil
hectares, to that in the Tercier Milenio proposal, 725 mil hectares from a
130 m dam, suggests that the actual dam planned is between 50 and 60 m
high. Any dam over 15 meters (50 feet) is classified as "High" by the
World Bank, so the Boca del Cerro Dam would definitely be a high dam.
My take on all this is that Chris is on target. The Usu' needs some
real protected status or the dam will just keep resurfacing.

Posted by Dave at September 06, 2002 12:02 AM