San Juan County residents who reside near flood plains of regional rivers are advised to prepare for the possibility of flooding.
Snowpack is reported to be at about 180% in the San Juan Basin, according to U.S. Department of Agriculture.
Day-to-day water levels fluctuate widely, but flow rates and gauge heights tend to steadily increase as snowpack melts.
Flood stage refers to when water levels of a body of water rise to a point that can cause inconvenience or damage. The “zero level” of a body of water is usually set at or near the stream or river bed or at the average level of standing bodies of water. Stream gauges measure the rise from zero level to establish the flood stage.
Flood advisories and warnings are linked to a body of water’s flood stage.
Aaron Chavez, executive director of the San Juan Water Commission, recently said the Animas River is the is of highest concern, and he is hopeful for gradual warming temperatures in order to avoid sudden, mass snowmelt and rapid evaporation.
The Animas River is considered to be in flood stage when it reaches a gauge height of 10 feet. The deepest area of the river, the gauge stage, is 6 feet, with a historical record of 5.82 feet for this time of year.
According to SNOFLO, the Farmington stream gauge reported flows on the Animas River of 1,360 cfs at a gauge stage of 6 feet on Monday. The ten-day streamflow average was 1,110 cfs, which includes a 3% decrease in flow from Sunday.
At the Cedar Hill stream gauge, the Animas River reached 1,970 cfs at a gauge stage of 6.53 feet on Monday, according to USGS data.
At one of the Farmington-area gauges U.S. Geological Survey data showed the San Juan River reached 2,400 cfs, with a gauge height at 3.13 feet. The La Plata River flow rate was at 99.3 cfs at a gauge stage of 3.81 feet on Monday.
Real-time data from the USGS, which are typically are recorded at 15 to 60 minute intervals, shows that the Four Corners region is in the 90th percentile in terms of daily streamflow.
Chavez said it was too early to tell exactly what kind of runoff to expect, but that it should be bountiful, compared to flow rates from the last decade.
Stream flows in San Juan County are expected to reach 91% of normal in April before increasing to an average of 168% through July, according to the National Resource Conservation Service’s April water supply outlook report.
The United States Drought Monitor’s statistics show the soil moisture content for most of San Juan County and southwest Colorado is at or near 100% of normal. USDM statistics also show that close to half of San Juan County is currently free of drought or abnormally dry designation.
Michele Truby Tillen, community development director for San Juan County, said there are 23,685 residences in the county that are designated as being in the Special Flood Hazard Area. This means the county is classified as Level 8, which makes homeowners eligible for a 10% discount on their homeowners insurance.
The National Flood Insurance Program’s Community Rating System designates a region’s flood hazard level based on several factors, including zoning and flood mitigation efforts. The lower the rating, the higher flood insurance discount a region may receive. The scale ranges from 10, which has the fewest mitigation factors, to 1, which has the most mitigation factors.
“We have awesome snowpack and that’s great as long as it stays up there,” Truby Tillen said. Her main fear is rapid melting due to unusually warm weather. She advised people to visit their website for information on real time water flow rates.
The National Weather Service offers these recommendations on preparing for flood threats:
- Create a communication plan with friends and family.
- Assemble an emergency kit.
- Know the risk of flooding for a specific location.
- Sign up for notifications from regional weather services.
- Prepare homes for flooding situations with sandbags.
- Prepare family members and pets for possible evacuation.
- Keep essential electronics charged.
- Leave the area when recommended.
When floods develop slowly, forecasters can anticipate where a flood will happen days or weeks before it occurs. In the Four Corners region, flash flooding is possible, with arroyos overflowing, unpaved roads washing out and highways becoming impassable.
After a flood, NWS recommends:
- Stay informed by local news for updated information on road conditions.
- Avoid flood areas to prevent hampering rescue and other emergency operations.
- Heed road closure and cautionary signage.
- Do not enter flood-damaged homes or buildings until cleared by authorities. Structures may be unsafe and electrical systems may be live.
Motorists are advised to never drive around barriers blocking a flooded road. The road may have collapsed beneath the water. According to NWS, as little as 6 inches of water can knock over an adult, 12 inches of rushing water can carry away most cars and 2 feet of flood water can move SUVs and trucks.
Local resident, Robert Crossley, fished the Animas River Monday near the confluence of the San Juan River and the Animas River. He said a friend of his reported that water at Navajo Dam was near the spillway on Sunday. Crossley also said this has been the best rainy season that he remembers in the last 10 years.
The city of Farmington posted on its Facebook page that sand and sandbags are available to residents to want to prepare for the spring runoff. The sandbag station is located on the southwest side of the parking lot off Vine Avenue behind the Farmington Recreation Center.
Residents should bring their own shovels to fill bags. If the blue bin containing sandbags runs low, residents are asked to call (505) 320-2993 to request it be refilled.