By Mary Alice Murphy
The New Mexico Central Arizona Project Entity held its February 2016 meeting on Tuesday, Feb. 2, at the Grant County Administration Center
No public comment was heard at the meeting.
Martha Cooper of The Nature Conservancy and alternate representative to the entity for the Upper Gila Irrigation Association presented a study of diversion structure options for the Cliff-Gila Valley, New Mexico.
"Some of its characteristics make the Gila River unique," Cooper said. "They include the variability in flows from 35,000 cubic feet per second to lows of 7 cfs. The low flows come in May and June after the snowmelt runoff is finished and before the monsoons arrive. These low flows are a period of stress for the ecosystem."
She said the river is a dynamic ecosystem, which changes channels periodically with floods. "That makes a static structure a challenge."
The Gila has a wide floodplain, as wide as 1,500 feet near Spar Canyon. She said the river also carries a large load of sediment in floods and deposits it.
"The irrigators need reliable flows during the dry season and during high flows," Cooper said. "They need reliable structures."
The study listed the disadvantages of the push up diversions used now, which include:
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