In November 2021, we built 8 postless BDAs as a demonstration project at Rancho Del Oso Pardo, a private ranch near Chama, NM. Structures were built using small diameter trees felled from nearby, overstocked slopes as well as rocks and sediments from adjacent to, and within the stream channel. BDA locations were chosen to maximize pooling, and to facilitate over-bank flow and flood plain reconnection.
This installation in Nabor Creek is located just upstream of the Sargent Wildlife Management Area boundary; a BDA installation is also planned for Nabor Creek within the Sargent WMA in 2022, which will support and increase the ecological impact of this project.
Goals for the project at Rancho del Oso Pardo include improving habitat for Rio Grande Cutthroat, which exist as a pure strain in the reach and are protected by a fish passage barrier located downstream in the Sargent WMA. The work will benefit Cutthroat populations through increased pools and backwater refugia, as a result of elevating the water table and instigating complex flow patterns that reduce velocity during high-flow events, and by bolstering the macroinvertebrate productivity through an expanded wetted area. The project will also aid in creating more readily inhabitable sites for beaver, and deposited sediment retention will promote carbon sequestration. The small diameter timber utilization coupled with the water table elevation increase will help to function as a fire break in the event of a wildfire.