Drought conditions remain virtually unchanged from a week ago, according to the latest U.S. Drought Monitor report. Most of the Arkansas River Basin is abnormally dry or drought-free with a few areas of moderate drought.

Precipitation

The CoCoRaHS (Community Collaborative Rain, Hail and Snow) Network reports the following precipitation amounts for the past week:

• Leadville - 0.10 inch.
• Buena Vista - 0.08-0.20 inch.
• Salida - 0.04 inch.
• ​Westcliffe - 0.39 inch.
• Cañon City - 0.20 inch.
• ​Walsenburg - 0.15 inch.
• Trinidad - 0.13 inch.
• Pueblo - 0.04 inch.
• Colorado Springs - 0.27-0.62 inch.
• Rocky Ford - 0.07 inch.​
• Pritchett - 0.03 inch.
• Lamar - 0.03 inch.

Reservoir Storage

The past week saw water storage in Pueblo Reservoir continue its gradual decline. At 179,153 acre-feet, the reservoir is 55.5 percent full. Water storage in Turquoise Lake decreased to 86,400.9 acre-feet or 66.8 percent full while the water level in Twin Lakes increased to 118,921 acre-feet, bringing  the reservoir to 84.3 percent  full. The U.S. Army Corps of Engineers reports the water level in John Martin Reservoir has declined to 13,857 acre-feet.

River Flows

Arkansas River flows haven't changed significantly over the past week but are generally lower. The gauge near Leadville reads 34.9 cfs, and the gauge below Granite dropped from 211 to 187 cfs after the Bureau of Reclamation reduced the Twin Lakes outflow today. The flow at the Wellsville gauge is 353 cfs while the flow at Cañon City is currently 281 cfs. The flow below Pueblo Reservoir has dropped to 76.9 cfs, and the gauge near Avondale reports 188 cfs. The Rocky Ford gauge reports 131 cfs, and flows are 51.7 cfs and 47.5 cfs below John Martin Reservoir and near Lamar, respectively.

Calling Water Rights

The number of calling water rights rights in the Arkansas Basin remains at 19, but most of the rights in play have changed since last week. The most senior right with a call is the Hardscrabble Ditch with an 1860 priority date on Hardscrabble Creek. An 1865 Hayden Supply Ditch priority (on Greenhorn Creek) is next in seniority, followed by the Hoenhe Ditch (Purgatoire River) and the O'Brien Ditch (Fourmile Creek), which also have 1865 priority dates.

Next in seniority are two water rights with 1866 priorities: the Baxter Pioneer Ditch on the Huerfano River and the Gonzales Ditch on the Apishapa River. The Gomez Ditch (1868) is calling for water on the Cucharas River, and the Talcott and Cotton Ditch (1872) is calling on Fountain Creek. The Camblin Ditch and the Cottonwood Irrigating Ditch, also with 1872 priority dates are calling for water on Hayden Creek and Cottonwood Creek, respectively. 

The Hill Ditch (1873) is calling for water on Howard Creek, and the Lamar Canal (1875) is the most senior calling water right on the Arkansas River mainstem. Next in seniority are the Seth Brown Ditch (1876) on Stout Creek, the Dotson Ditch No. 1 (1881) on the St. Charles River, the North Fork Ditch (1882) on the South Arkansas River, and the Fort Lyon Canal (1884) on the mainstem. Rounding out this week's calling water rights are the 1885 Buffalo Canal right, the 1889 X-Y Irrigating Ditch right and the 1949 Arkansas River Compact.