FLORENCE
– In February 2005, the Schnepf Road Bridge across Queen Creek in
northern Pinal County sustained damage after a huge rain storm.The bridge connects Ocotillo Road on the north end to Combs Road on the south.
Heavy,
steady runoff caused by the intensity of the storm and the erosion and
scouring of a large amount of rocks and boulders in the bed of the
creek exposed key support structures.In March
2005, Pinal County Public Works officials closed the bridge after
engineering studies revealed evidence that the bridge could be unsafe.By late 2005, a full engineering assessment determined that replacement of the bridge was the only option.
“When the bridge was built, there was about seven feet between the flow line of the channel and the bottom of the bridge.Now there’s about 20 feet,” Public Works Director Greg Stanley explained.“Steady
rains, changes in land use in the surrounding area, nearby gravel
mining and a dam at the Central Arizona Project canal changed the flow
of water in the area, ultimately affecting the structural integrity of
the bridge.”
Simply shoring up the bridge was not an option, Stanley said.The bridge would still be subjected to the force of the water.
Preliminary design work concluded that a reinforced concrete box culvert design would provide the best long term solution.To visualize this design, imagine one large rectangular concrete box with a common floor, walls and ceiling.Then add two vertical walls breaking it into three tunnel-like chambers.Traffic would move across the “ceiling” of the structure and storm water run-off would flow through the three chambers.
Pinal County submitted the design and a request for federal funds to the Federal Emergency Management Agency (FEMA).Fast forward to today.FEMA
has approved the funding for a new bridge with one lane each way and a
center turn lane to better manage traffic flow on either end of the
bridge.
FEMA
approved $1,687,376 from its Public Assistance Program to assist Pinal
County and the State of Arizona in the replacement of the crossing.The FEMA funds constitute 75 percent of the $2,249,835 in total eligible costs for the project.The remaining funds will come from the state and county.
“Significant design work is underway and we anticipate finalizing the plans by the end of August,” Stanley said.“At that time, we can solicit bids for construction.Residents in the area should see significant construction in the area starting in early 2009.Our target for completion is late 2009.”
FEMA Region IX Infrastructure Branch Chief for Response and Recovery William Roche said,“We
are pleased that public assistance funds could be used to help restore
a vital link in the Pinal County transportation system.”
Stanley
said timelines are still a little blurry because his staff must
coordinate the timing of the construction with companies that have
utility infrastructure in and around the bridge.Roads and bridges are commonly used for the routing of utility infrastructure such as electric, gas, fiberoptic lines and cable.
FEMA,
The Arizona Division of Emergency Management, Pinal County Public Works
and area officials all agreed that residents in the area will have a
better, wider, safer bridge.Approximately 6,000 vehicles used the bridge each day.The new box culvert crossing will be able to accommodate the County’s present and anticipated growth for decades to come.
