RESTORING BOLLINGER MILL: FLOODWATERS, INSECTS, TIMES DAMAGE HISTORIC BRIDGE

Jack Smoot, historic site administrator at Bollinger Mill State Historic Site in Burfordville, stood inside the covered bridge which is closed to the public.

exterior covered bridge:

The 140-foot covered bridge at Burfordville has been closed to vehicular traffic since the mid-1980s.

use small: bridge with mill

The Bollinger Mill at Burfordville is situated next to the covered bridge.

bridge key:

The historic Burfordville covered bridge will soon get the repairs it so badly needs.

The Missouri Department of Natural Resources has awarded a contract for repairs to the bridge to the St. Louis Bridge Construction Co. of Arnold.

The bridge, completed around 1868, has been in need of repair for some time. It was closed to vehicle traffic in the mid-1980s and to pedestrian traffic in 1991.

The major structural damage to the bridge has been to the chords, the lower members of the trusses that support the weight of the entire bridge. Repeated flooding, along with insect infestation, has weakened the undercarriage of the 140-foot span.

Jack Smoot, historic site administrator at Bollinger Mill State Historic Site where the bridge is located, said the bridge was moved off its foundation on the east end by the flood of May 1986. That was the flood that destroyed the mill at Old Appleton.

Floodwaters that year were 57 inches deep on the main floor of the mill, Smoot said.

During the flood of 1993, he said, water was 50 inches deep on the floor of the mill, and last May 30 water was 38 inches deep. These floods also reached the lower portion of the bridge.

"Such flooding is where the real damage to the bridge occurs," Smoot said. "Flooding defeats the purpose of covering the bridge, which is to protect the main timbers of the bridge from rot and moisture."

The whole purpose of the roof and siding, said Smoot, was to keep the bridge trusses and timbers dry. Flooding introduces tremendous moisture to the lower timbers, and the flooding and drying cycle has introduced rot.

Smoot said that planners had originally wanted to raise the bridge permanently to get it above floodwaters, but the cost of doing so was prohibitive. The original yellow poplar timbers would be replaced by treated Douglas fir, which will be less susceptible to rot.

Another concern of engineers was damage to the keys, which look like "giant wood staples" that connect the joints of the timbers in the chords. The new keys will be stainless steel plates, with an oak facade on the outside to retain the original appearance of the bridge.

"Because the bridge is listed in the National Register of Historic Places," Smoot said, "we don't want to do anything to destroy the original integrity of the design."

The cost of the repair contract is $532,244. The contract requires that the work be done by mid-June. Much of the assembly work will take place next winter inside the construction company's shop, and installation will take place next spring.

Smoot said that preserving the bridge is very important to the Bollinger Mill site.

"The bridge distinguishes this site," he said. "The juxtaposition of the covered bridge and an old grist mill, both 19th-century structures, is an unusual combination. The picturesque nature of the setting would be damaged if the bridge were lost."

Don Manson, St. Louis Bridge Co. project manager for the restoration, said that his company has done quite a bit of historical restoration work in St. Louis and other areas. The firm has done a lot of wood and timber restoration, especially in bridges.

Manson said that people probably think the bridge is in worse shape than it actually is. It has had water and insect damage but that the damage is mainly to the bottom chords.

"The bridge should last for many years with the treated timber," Manson said. "The treated timber will keep the insects and weather out."