Closed Basin Project

[2] It contains the towns of Center, Hooper, Moffat, Mosca and Saguache and the Great Sand Dunes National Park and Preserve.

The lowest part of the basin extends from the San Luis lakes north to the Blanca Wildlife Habitat Area.

[1] The channel has a PVC lining covered with 12 to 16 inches (300 to 410 mm) of aggregate and fill, with a capacity that expands from 45 to 160 cubic feet (1.3 to 4.5 m3) per second from north to south.

Trees have been plated along the channel in the areas that are most susceptible to wind erosion, watered through drip irrigation systems.

More than 132 observation wells were used as of 2012[update] to measure water level or pressure from the aquifers, with the data used to ensure the project stays within the authorized drawdown limits.

[2] As of 2016, 11 of the wells had been shut down because their output exceeded the limit of 350 parts per million (ppm) for total dissolved solids and therefore cannot be discharged into the Rio Grande under the river compact.