on the night of March 2–3, 1938 a flood of poured out of the mountains and into San Gabriel Reservoir. San Gabriel Dam was able to knock about off the peak of the flood. Further downstream, Morris Reservoir was able to absorb roughly , reducing the flood to less than half of what it would have been if not for the dams. Water management Water stored behind San Gabriel Dam is an important source for groundwater recharge during the dry season of April through October. Water from San Gabriel, Cogswell and Morris Dams is released gradually through the dry months to spreading grounds at San Gabriel Canyon (Azusa) and Peck Basin (near Arcadia), where it percolates into the local groundwater basin. Dam operations are coordinated by the San Gabriel River Water Committee (Committee of Nine), established in 1889 to represent water-rights holders on the San Gabriel River and with rights to of river water; and the San Gabriel Valley Protective Association, which has rights to all water flows above 97,700 acre-feet as well as all storage space in San Gabriel, Cogswell and Morris Dams. The large reservoir, known as San Gabriel Reservoir No. 1, is nearly long when full. The reservoir stores of water when full, creating one of Southern California's largest instream reservoirs. This is 17% less than the original capacity of when the dam was first built, because sedimentation has reduced the water volume. Interest in sediment removal began in the 1980s, after several major wildfires in the San Gabriel Mountains and subsequent flooding caused millions of cubic yards of sediment to wash into the reservoir. The reservoir was dewatered in 2004 to allow for sediment removal, but work was delayed after heavy rains during the winter of 2004–2005 refilled the reservoir. Disposal of the removed sediment has been a contentious issue. The 2005 sediment removal project stored about of sediment in a nearby canyon, but this is now prohibited due to environmental and safety issues. Another option would have been to truck the sediment to local beaches for replenishment, but this has also been banned by the California Coastal Commission. Currently, most of the sediment is sold for building material or ends up as landfill, but these options are highly limited. Flood control releases are coordinated in conjunction with the other mountain dams, Morris and Cogswell; and with Santa Fe and Whittier Narrows Dams on the lower