Precipitation for the month of September, as measured at the SNOTEL sites operated by NRCS, was reported at approximately 231% of average (4.8 inches) for the North Platte River basin. The total precipitation at the end of WY2013 as measured at the Snotel sites was 98% of average.
Streamflows at the North Platte River near Northgate gage station were well below average for the months of August and into the early part of September. However after about September 10 the flows increased to well above average. By way of example, the daily average streamflows for the North Platte near Northgate were 119 cfs and 237 cfs for August and September, respectively, while the historic daily average is 257 cfs and 145 cfs, respectively.
The reservoirs used primarily for irrigation in the basin were down approximately 19,700 AF from full going into the spring of 2013. As a result, the State of Colorado closely tracked the amount of water stored for irrigation purposes in an effort to ensure the 17,000 AF limit would not be exceeded. As of the middle of July approximately 16,700 AF had been stored for irrigation purposes. Because this number was so close to the 17,000 AF limit, letters were sent in August to all owners of reservoirs used for irrigation requesting that they contact our office if they desired to store any water before the end of September and were informed that after September 30, 2013 they could begin refilling their reservoirs as needed if water was physically available. Only one water user contacted our office and this individual was told he could store water in all of his reservoirs. The preliminary end of water year number for storage is approximately 17,500 AF; and exceedance of Colorado’s limit by approximately 500 AF. This over storage occurred in the month of September. Colorado would like to discuss with the NPDC how best to address this over storage.
The preliminary numbers for the transbasin diversions that occurred in 2013 were 4,984 AF by the Michigan Ditch and the amount diverted by the Cameron Pass Ditch is unknown at this time.