Engineers Design New, Improved Routes
Frank McIllwain remembers the days when cities and developers commissioned the construction of new roads and routes, in undeveloped areas.
According to him, those were the good ol’ days.
But times have changed and the Northwest Arkansas’ rapid growth has created an urgent demand for improved roads and better infrastructure throughout Benton and Washington counties. That means McIllwain, a transportation engineer with Garver Engineers LLC, and others like him are feverishly finding ways to expand, reconstruct and improve existing city roads, corridors and state highways.
Four major citiess along the Interstate 540 corridor have multiple road expansion and improvement projects under way and dozens of improvement projects are still on the drawing board.
As taxpayers continue to express their desire for better roadways, cities are increasingly looking to local engineering firms to transform existing roads into new, multi-lane corridors and thoroughfares.
Bentonville, Rogers, Springdale and Fayetteville have a combined $252 million in bond programs and sales tax increases dedicated to funding city road projects.
The Northwest Arkansas Regional Planning Commission lists an additional $146.9 million slated for state highway projects, funded by both the cities and the state, schedule to take place from fiscal 2008 to fiscal 2010.
Combined, the four cities have about 50 different existing road projects in construction or design phases.
But the process of taking a road from two lanes to five lanes is no easy task and transportation engineers often spend more than a year creating a new roadway and overcoming the hundreds of hurdles that present themselves along the way.
“There is a lot that goes into widening a road, there are a lot of entities that have to coordinate on each project and a lot of details that require attention,” said McIllwain, who designed two phases of Springdale’s new southern corridor. “Creating a new two-mile road in the middle of the desert is easier than building or expanding a half-mile of road in the middle of town.”
Caution: High Costs Ahead
There is no Wal-Mart-like price tag for road expansion. Prices are always high. Always.
Road improvements carry million dollar figures and cities are increasingly turning to taxpayers and the state and federal government to help carry the cost.
According to data from The Arkansas State Highway Transportation Department, it costs about $3.75 million per mile to widen an existing, urban road from two lanes to five lanes.
And reconstruction of an existing road, which involves new drainage, surfacing and/or minor widening, costs $800,000 per lane, per mile.
The three phases of Springdale’s southern corridor will cost the city about $29 million to complete. Add to that the expansion and re-routing of Wagon Wheel Road to create a northern corridor and the widening of Huntsville Road east of U.S. Highway 71-B to complete the city’s center corridor, and Springdale is looking at a $61.7 million price tag for the expansion of three east-west streets.
Ron Petrie, Fayetteville city engineer, said the $15.5 million cost estimate for the widening of Arkansas Highway 265 from Arkansas Highway 45 to Joyce Boulevard, is a project many drivers would like to see completed but more than the city can afford right now.
The project would require massive property acquisition and relocation of all utilities. Neither come cheap.
And it’s not just communities in Northwest Arkansas grappling with the issue of insufficient infrastructure.
The ASHTD estimates that by 2016, more than 500 miles of the state’s highway system will need to be widened, a project that comes with a $1.6 billion price tag. Bridge rehabilitation or replacement will cost the state an additional $1.6 billion by 2016.
All in all, the state estimates it will spend about $8.8 billion on highway preservation between 2006 and 2016.
Warning: Men at Work
Michael Burns, vice president of transportation for Crafton Tull Sparks & Associates, said an existing road project must go through three distinct steps before it can be given to contractors for construction bids.
Projects start on the drawing board and transportation engineers gather information from utility locations to elevations, drainage needs, property ownership and neighboring subdivision plats before a line is drawn.
Engineers have to look at both the horizontal and vertical alignment of a project said Kevin Beaumont, project manager for McClelland Consulting Engineers Inc.
Horizontal alignment includes working through property acquisition issues and finding a centerline that leaves an equal amount of property on both sides of the road.
Rights-of-way have to be purchased by the city for a new road.
Terry England, director of customer service for Arkansas Western Gas Co., said once the project engineer secures a route for the road, the utility companies begin finding new locations for their wires, cable and pipes.
“The number one issue for us is obtaining the right-of-way for new pipe locations,” said England. “Our philosophy is to maintain as many of our facilities on private rights-of-way as possible but sometimes we work in concert with the cities to secure property for our lines.”
Water and sewer lines are the first to be relocated, followed by gas and then cable. Gas pipelines must be located at least 10 feet away from all sewer lines.
England said AWG must maintain service for all customers in the area, which often poses its own challenges because high-pressure gas cannot be disconnected.
The company, which has about 100,000 customers in the two-county area, has had to increase its contractor base for new construction projects so that it can use its in-house crew for road expansion or relocation projects.
“We have been extremely busy the past couple of years and we have tried to stay ahead of the curve,” England said. “But that’s been hard with so many projects under construction right now.”
Burns, who created the new Perry Road overpass in south Rogers, said that an existing creek flowing through the new construction site posed a unique horizontal challenge.
Burns had to work with the Army Corps of Engineers to ensure that the creek remained undisturbed during construction and that it was rerouted in a way that it could continue to flow.
The first phase also involves tackling vertical alignment issues.
Vertical alignment involves the peaks and troughs of the proposed road and drainage from the new project.
Beaumont said he encountered numerous vertical alignment issues while creating the plans for the Wagon Wheel corridor.
A large hill on the north side of Wagon Wheel caused significant run-off into the area where the road was to be rerouted. Beaumont had to design drainage channels to manage and discard the water.
And because the road is going to be used as a corridor, Beaumont said he had to keep the peaks, troughs and curves to a minimum so that it didn’t affect the speed limit for the road.
“In phase two of Wagon Wheel, by 40th Street, there are some very pronounced peaks and troughs,” Beaumont said. “With the new road being used as a principal arterial we had to cut some high points out and fill in some low points. The city prefers a three-to-one grade on all corridor roads so that the speed limit can be increased.”
Once a plan is secured and approved by the city, it is submitted to the ASHTD for approval.
At that point, Burns said, a plan is considered 30 percent complete.
Once the state gives the plans its approval, engineers are tasked with mapping out alternative traffic routes while the road is under construction and finding ways to mitigate erosion for construction.
The state does not like construction projects impeding traffic, Burns said. He had to find ways for at least two lanes of I-540 to remain open during all of the overpass construction.
When engineers find solutions to those problems, the plans are resubmitted to ASHTD and are considered 60 percent complete.
Glen Bolick, a public information officer with the ASHTD, said that state engineers double check all figures, measurements and drawings to ensure the plans are sound.
Once the local engineer receives the plans from the state for the second time, a final check is performed on all renderings and numbers and the plans are resent to the state for final approval.
At that point the job is complete for the engineer but construction has yet to begin and it will be at least one year before drivers see a new and improved road.