Update: Chimney Rock National Monument has reopened.
Original: Pagosa Country has experienced both record-low river levels and flooding that caused closures over the last week, including the ongoing closure of Chimney Rock National Monument.
The San Juan River in downtown Pagosa Springs hit a new record low flow on Thursday, Sept 10, falling below 12 cubic feet per second (cfs), before trending back up with this week’s rains.
On Friday, Sept. 11, the Piedra River near Arboles set a new record low flow of 10.4 cfs. The previous record for that day was set in 2018 at 17.3 cfs.
By Wednesday morning, the San Juan River was flowing above 60 cfs, according to the U.S. Geological Survey (USGS), and had an instantaneous reading over 55.1 cfs at 2 p.m.
According to 90 water years of USGS records, the record low flow for Sept. 16 was set in 2018 at 12.9 cfs. The record high was recorded in 1970 at 1,190 cfs.
The median cfs for that date is 85 cfs, and the mean is 144 cfs.
As of 2 p.m. on Wednesday, the Piedra River was flowing at a rate of 25.2 cfs.
According to 63 water years of USGS records, the record low for that date was set in 2018 at 11.2 cfs, and the record high was set in 1970 at 1,630 cfs. The mean flow for that date is 216 cfs, and the median flow is 123 cfs.
Heavy rain and drought
Pagosa County experienced multiple rain events beginning on Monday, Sept. 14, with reports from the Community Collaborative Rain, Hail and Snow Network in Archuleta County showing anywhere from just under an inch to more than 2 inches of rain received from Monday to Wednesday.
The most recent drought map released by the U.S. Drought Monitor was published on Sept. 10, before the area’s most recent rain events, and shows just over 50 percent of Archuleta County being in a stage three, extreme drought.
That was up from just over 22 percent of the county falling under extreme drought as of Sept. 1.
For more information and to see an updated drought map, visit droughtmonitor.unl.edu/CurrentMap/StateDroughtMonitor.aspx?fips_08007.
Closures
Some of the heaviest rains were reported in the Arboles and Allison areas of Archuleta County.
During a work session held by the Archuleta County Board of County Commissioners on Tuesday, Sept. 15, Public Works Director Mike Torres indicated that crews worked overnight from Monday to Tuesday clearing flood debris on parts of County Road 500.
The recent rains and flooding also forced the U.S. Forest Service to close Chimney Rock National Monument until cleanup of mud and debris is completed.
According to a Sept. 15 press release from the Forest Service, “Chimney Rock National Monument is closed effective immediately and will reopen once flood damage has been repaired. During the evening of September 14, severe thunderstorms impacted several areas of the Monument, sending mud, rocks, and debris across roadways, parking lots, and paths.
“Due to the threat of additional heavy rain in the coming days, the monument will remain closed until the threat of flash flooding passes this week and the mud and debris can be cleaned up. Road crews and engineers are assessing repair needs and Monument staff are shoveling mud and rocks out of parking lots and pathways.”
It also notes that an announcement will be made when the monument reopens.
Forecast
According to a press release from AccuWeather, “Tropical moisture in the Gulf of California is surging into the southwestern U.S. bringing heavy rain and thunderstorms across the area through Friday, with the Four Corners region facing the greatest risk as AccuWeather warns this storm could bring as much as a foot of rain in some localized spots.”
The National Weather Service (NWS) issued a flood watch for Pagosa Springs starting yesterday, Wednesday afternoon, and lasting until midnight tonight, Thursday, Sept. 17.
More showers are expected through Saturday, Sept. 19, with the NWS predicting the greatest chance of showers Thursday night, Sept. 17, and Friday morning, Sept. 18.
Highs through the weekend are expected to range from 68 degrees on Thursday up to 76 degrees on Saturday. Lows are expected to range anywhere from the high 30s to low 40s.
clayton@pagosasun.com
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