A cylindrical gauge at the Highway F bridge south of Pacific tells state and federal water agencies the level and flow of the Meramec River.
Part of a system that was established to warn when water was rising, the Pacific gauge is now reporting levels approaching low water records.
The small tube-like device, with a spiky antenna, measures the level of the river and relays data to the U.S. Army Corps of Engineers, National Weather Service and the Missouri Department of Conservation. Ham radio operators and fishing groups also pay attention to the data.
Meramec River Gauge PCFM7 is located on the south side of the Highway F bridge 50.5 miles from the mouth of the Meramec. It sits 10 feet downstream from the east end of the bridge of the right bank.
The Army Corps of Engineers, which owns the device, has been measuring the levels of the river since the devastating flood of 1915.
The river level measuring system was put into effect largely to measure advancing floodwater. The highest level measured on the Pacific gauge was 28.7 feet in 1994. Flood stage is 15 feet.
On July 27, the gauge showed that the river level at Pacific was -1.96 and had changed 0.00 feet within the previous 24 hours. The lowest level recorded here was -2.50 on Aug. 4, 1972.
The Meramec River may not be dangerously low yet, but everyone is watching the data sent by the small electronic gauge. The device also measures the rate of discharge, which was 292 cubic feet per second on July 26, the same day the -1.97 level was reported.
The average median daily discharge for the past 92 years has been 1,000 cubic feet per second.
The highest reported discharge was 19,300 cubic feet per second in 1981. The lowest was 284 cubic feet per second in 1934. This puts current readings near the lowest since discharge rates have been measured.
The low river levels are uncovering some sandbars that are causing recreational boaters and fishermen some concerns.
The Missouri Department of Conservation has placed a ban on campfires and other open burning at conservation areas next to the river such as Pacific Palisades, Catawissa Conservation Area and Robertsville State Park.
Among other agencies that read the gauge every day are American Anglers, which posts online fishing information. Some fishermen are reporting the dangers of stepping onto the tip end of a sandbar.
The Meramec Ambulance District has not had a specific heat-related emergency relating to low water, Chief Christine Neal said, but the agency remains open to assist any residents needing relief from the heat.
“We can keep them cool during the daytime and give them plenty of water to drink,” Neal said.
The ambulance district rolls one ambulance on every fire call.
“We are there to provide assistance for any victims of the fire,” Neal said, “but also to provide relief for the firefighters who have to be rotated off the fire lines. We take vital signs, place a cold wet towel on their necks and give them plenty of water to drink.”
Fire Marshal Ken Prichard said the Pacific Fire District has not suffered any impact from either the high temperatures or dwindling surface water.
“We have one or two little ponds that we would draw from if there was a fire nearby,” Prichard said. “I need to take a drive by and see what they look like. But for the most part we have not had a problem.
One agency that may benefit from the low water council is the Open Space Council, which organizes the annual clean stream cleanup. Last year volunteers removed 390 cubic yards of trash, 2,000 tires and 50,000 pounds of metal from the Meramec River.
On Saturday, Aug. 25, the 45th annual Operation Clean Stream will take place. Volunteers will meet at Greentree Park in Kirkwood at 9 a.m.
The city of Pacific, which has the benefit of having deep wells, is also watching the dwindling ground water.
“The drawing down of wells naturally affects our wells,” said Ben Boedges, Pacific Water Department supervisor. “To date our wells are down about five feet which is not a problem at their normal depth of 70 feet, but we’re watching it.”