Río Atoyac

In mid-October, 2009 I floated much of RIo Atoyac with my wife Barbara Conboy over 3 days. The river originates in a spring upstream of Potrero Nuevo. From there to Atoyac the river has a medium gradient and some gorgy character and perhaps some smaller falls. We did not run this part. Just downstream of the town of Atoyac the river enters a class V gorge with a ~15 m falls coming just after a 2 m falls. This is followed by several class IV-V rapids. The Gruta de Atoyac is on RL a few hundred meters downstream of the falls. This gruta leads about 14 km to exit at Paso del Macho. There is a good 0.5 km trail down to the gruta from the dirt road (converted from old railway line). We put-in here. After three more class IV-V rapids, the river exits the high canyon and a big tributary comes in from RL. From this point down to the next bridge (10km) the river remains in gorge and canyon and is primarily class III with a couple of IVs and one V (about 9 km into the run; it consists of several drops in a gorge starting at a travertine springs on RR). The class V section can be portaged on a trail RR. The road bridge is called Puente Chico.
The next 28 km section from Puente Chico to Puente Palo Amarillo starts with 2.5 km of class III-IV and a few portages/Vs of boulder-choked drops. Then Rio Seco joins on RL and the river is great fun class III for the remaining 26 km to the new Palo Amarillo bridge. This section is similar to the main Jalcomulco but rapids are more frequent initially.
Rocky