SWSIReportJuly2008

• Title: Colorado Water Supply Conditions Update
• Date: 7/25/2008
• Description: Water Availability Task Force Meeting Materials
• Basin: Statewide
• Drought Mitigation - Doc Type: Presentation

RIO GRANDE BASIN
Basinwide Conditions Assessment
The SWSI value for the month was 1.6. Flow at the
gaging station Rio Grande near Del Norte averaged 3829 cfs
(125% of normal). The Conejos River near Mogote had a
mean flow of 1452 cfs (112% of normal). Streamflow in the
upper Rio Grande basin was erratic during early June as
temperatures fluctuated widely, but settled to the normal
slow decline as the winter snowpack melts out. The higher
elevations and the Valley floor received below average
precipitation during June, and for the fourth consecutive
month. Storage in Platoro, Rio Grande, and Santa Maria
reservoirs totaled 83% of normal as of the end of June.
Outlook
As the month of June came to a close, some
monsoonal-type activity began, replacing the dry, windy
conditions of April, May and early June. NWS 90-day
forecasts for July through September suggest higher than
normal temperatures and a chance for normal precipitation.
AdministrativelManagement Concerns
Some of the upper Rio Grande basin streamflows have
not been as prolific as forecasted. The result is the lessening of
water right curtailment on the Rio Grande and the Conejos to
meet the Rio Grande Compact delivery obligation.
The vast network of satellite-monitored gauging
stations in Division 3 is a great benefit to water administrators,
farmers, ranchers, and recreators. The Colorado Division of
Water Resources website at www.water.state.co.us provides
easy access to over 80 satellite-monitored gauges in Division 3
alone. The gauges include 57 local creeks and rivers, 19
ditches and canals, 7 reservoirs, and access to an additional 20
stations monitored by the U.S. Geological Survey in Colorado
and New Mexico essential for administration of the Rio Grande
and Costilla Creek Compacts.
Current flows can be monitored against historic
average daily flows, with many stations having over 50 years of
data. Review of the recent streamflow data in the upper Rio
Grande basin reveals a hodge-podge of conditions. The
mainstem of the Rio Grande and the Conejos River and their
tributaries have experienced above-average flow during the
2008 runoff. The Alamosa and LaJara Creek drainages have
also been good producers. The Saguache, La Garita and
Carnero area has been disappointing, with below average
flows. On the east side, 2008 volumes have been very random,
with some streams such as Ute, Rito Alto, and Cottonwood
Creeks all above normal, yet Crestone and Sangre de Cristo
Creeks below average. In summary, what was shaping up to
be a very high runoff year for this portion of the state, has in
reality produced spotty results.
Public Use Impacts
Finally, some consistently sunny conditions favored the
farmers and ranchers aiding the growth of crops and grazing
land during the last three weeks of June. The first cutting of
hay and alfalfa yielded a bit below normal due to the cold
temperatures during May and early June.
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RIO GRANDE BASIN SV~61 HISTORY
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