Bob Parmenter, the chief scientist at the Valles Caldera National Preserve, provided some insight today about our previous post, describing a blackened San Antonio River that smelled of ash this weekend, as well as a similarly dark and murky East Fork of the Jemez River.
Dr. Parmenter left the following voicemail with VallesCaldera.com today:
[The black flow coming out of the San Antonio] was an ash flow from a flash flood that originated up in Indios Creek Canyon. We had kind of hoped that we wouldn’t get hit that hard with a thunderstorm but we’ve actually had four floods come out of there since the 25th of July — which was the first one — and each one of those brings with it a large amount of ash and organic debris coming down from the burned areas of these watersheds. We’ve also had floods come off into the Rio San Antonio from Cerro Santa Rosa and Cerro Abrigo, and there’s been some ash flows into the Jaramillo Creek Area, which of course eventually will work its way down to the East Fork of the Jemez.
The areas that have not been hit are the upper East Fork of the Jemez in the Valle Grande and the Valle Toledo. The large expanses of grassland have mitigated that because the ash flows coming down the mountains spread out, and the grass filters it, and eventually stops the ash slurry from reaching the stream. So, at least at this point in time, those areas are OK.
But, yes, the Rio San Antonio has had major ash flows down that stream through the Rio San Antonio — through the Valle San Antonio — and we’ve noticed a lot of fish kills along the way, so that’s why we’ve pretty much closed fishing on the Preserve for the rest of the summer.

