Colorado and the Arkansas River Basin saw the first snowfall of the season in October. Drought severity generally lessened across the state and did not change significantly in the Ark Basin, according to the latest U.S. Drought Monitor report. 

Precipitation

The CoCoRaHS (Community Collaborative Rain, Hail and Snow) Network reports the following precipitation amounts for the month of October:

• Leadville - 1.32 inches.
• Buena Vista -  0.64 inch.
• Salida - 0.43 inch.
• ​Westcliffe - 0.46 inch.
• Cañon City - 0.13 inch.
• ​Walsenburg - 1.05 inches.
• Trinidad - 1.91 inches.
• Pueblo - 0.09-0.43 inch.
• Colorado Springs - 0.14-0.56 inch.
• Rocky Ford - 0.11 inch.​
• Pritchett - 0.16  inch.
• Lamar - 0.26.

Snowpack

Early season snowpack is trending above average for the Arkansas Basin with the latest NRCS Snowpack Telemetry (SNOTEL) report showing basin-wide snowpack at 125 percent of median for snow-water equivalent (SWE). The highest reading is currently at Hayden Pass, where the SNOTEL station shows the SWE at 2.5 inches.

Reservoir Storage

Water storage in Pueblo Reservoir trended slightly lower in October, from 178,299 acre-feet to 177, 342 acre-feet, leaving the Fry-Ark Project storage vessel 54.9 percent full. Water storage in Turquoise Lake also saw a slight drop to 85,368.5  acre-feet or 66.6 percent full, while the water level in Twin Lakes edged up to 120,899 acre-feet, bringing the reservoir to 85.7 percent  full. The U.S. Army Corps of Engineers reports the water level in John Martin Reservoir dropped to 11,442 acre-feet.

River Flows

October saw Arkansas River flows decrease in the upper basin and lower basin with increased flows in between – Cañon City to Avondale. The flow near Leadville dropped to 24.3 cfs, the gauge at Granite currently reads 111 cfs, and the flow at Wellsville is 408 cfs. Flows at Cañon City and below Pueblo Reservoir are up from the end of September at 375 cfs and 211 cfs, respectively. The river flow near Avondale has also increased, to 437 cfs, while the flow at Rocky Ford dropped to 148 cfs. Flows have dropped to 11.8 cfs below John Martin Reservoir and 10.1 cfs near Lamar.

Calling Water Rights

The number of calling water rights in the Arkansas Basin has dropped to 15 (from 20 at the end of September). The most senior calling right is the Cañon Heights Ditch right with an 1863 priority date on Fourmile Creek. Next in priority are the Model Ditch on the Purgatoire River and the Francisco Daigre Mill right on the Cucharas River, both with 1864 priority dates. Next in seniority is the Hayden Supply Ditch on Greenhorn Creek with an 1865 priority date.

Three 1866 rights are calling for water – the Walsenburg Ditch on the Cucharas River, the Bannister Ditch on Fountain Creek and the Gonzales Ditch on the Apishapa River. Next in seniority are the Coleman Ditch on Hardscrabble Creek (1867), the Fernandez Ditch on Turkey Creek (1868) and the Upper Huerfano No. 2 right on the Huerfano River (1869).

Additional calls include:

• Lamar Canal on the Arkansas River mainstem (1875). 
• Catlin Canal on the mainstem (1884).
• Buffalo Canal on the mainstem (1885).
• X-Y Irrigating Ditch on the mainstem (1889).

The Arkansas River Compact call on the mainstem at the Kansas state line.