Sarah Mildred Long Bridge replacement project
Innovation in motion
By Joyce Noel Taylor, MaineDOT Chief Engineer
Mainers pride ourselves on our Yankee ingenuity and frugality, and rightly so. At MaineDOT, it’s part of our very fabric; our mission is “to responsibly provide our customers the safest and most reliable transportation system possible given available resources.” Working within available resources and being responsible requires innovation and vision. The synergy of forward thinking and innovation is currently on display in southern Maine, spanning the waters between Maine and New Hampshire.
The existing 74-year old Sarah Mildred Long Bridge, that carries the U.S. Route 1 Bypass over the Piscataqua River between Kittery, Maine and Portsmouth, New Hampshire, is in poor condition and not doing its job. Only small trucks can use it today; it has been limited to 20-ton vehicles since 2009. The bridge is number one on New Hampshire’s “Red List” of bridges. Simply put, the bridge is at the end of its life.
Perhaps more importantly, the Sarah Mildred Long Bridge has huge economic value. It services highway, rail and marine navigation and is the principal backup to I-95 in the event of disruption of service on the high-level Piscataqua River Bridge.
Together, the Piscataqua River and Sarah Mildred Long bridges are probably the two most important bridges to Maine. Combined, they re-present an estimated $8.4 billion per year to Maine’s economy and carry 62 percent of all large trucks crossing Maine borders. The rail portion of Sarah Mildred Long provides the only viable transportation mode for the Portsmouth Naval Shipyard to ship spent nuclear fuel from its servicing operations of the U.S. Navy’s fleet of nuclear submarines. So the challenge is clear: what to do about a big, old, complex, structurally deficient, moveable bridge with high economic value.
The solution required innovation in design, funding and project delivery. Regarding design, the proposed new bridge will feature an integrated rail-highway deck for the lift span structure. The lift span will rise for tall ships and will lower for rail use. The innovation will allow for a 64-percent reduction in the number of required bridge lifts. This design will result in the elimination of a retractable rail span on the current Sarah Mildred Long, less wear-and-tear, fewer automobile traffic accidents and delays, and better air quality from reduced vehicle idling for the rest of this century.
Although we continue to work hard to manage costs, the sheer size and complexity of the Sarah Mildred Long project means that this will be the most expensive bridge ever constructed by MaineDOT. The current replacement construction cost target is $158.5 million. Including design and property acquisition costs that already have been funded, the total current project cost target is $172 million. So innovation in funding is necessary as well. Thirty million dollars of Maine’s funding is being derived from a transfer of the southerly two miles of I-95 from MaineDOT to the Maine Turnpike Authority. Without these two bridges, the turnpike would be essentially out of business. Further, MaineDOT and NHDOT recently reapplied for a $25 million ($12.5 million per state) federal TIGER grant (Transportation Investments Generating Economic Recovery) for the cost of the rail portion of the bridge, as rail costs are not eligible for traditional federal highway funding.
The innovation doesn’t end with the design or funding. MaineDOT is using a cutting-edge project delivery method known as construction manager/general contractor (CM/GC). CM/GC is a project delivery method that allows MaineDOT to engage a contractor, initially known as a “construction manager,” to provide early constructability input during the design process. It is being promoted by the Federal Highway Administration as part of their Every Day Counts initiative. The intent is to form a partnership among the project owner, the contractor and the designer early in the process to manage risk and troubleshoot challenges. A stakeholders’ group of local residents is also an integral partner to ensure the bridge design reflects the interests, personality and aesthetics of the community, whenever practicable.
MaineDOT previously has used the CM/GC delivery method on only two occasions. The first project was the award-winning Penobscot Narrows Bridge between Prospect and Verona Island that opened to traffic in 2006. This $89 million project, required due to unexpected deterioration of the main support cables of the old Waldo-Hancock suspension bridge, went from concept to completion in only 42 months. The second use of CM/GC occurred when Tropical Storm Irene washed out two bridges on Route 27 in Carrabasset Valley in the late summer of 2011. Working closely with our contractor, temporary bridges were functional in nine days, and two permanent, weather-resistant bridges were open before the economically-important ski season started – in an amazing 82 days.
CM/GC is a useful project development tool, but it is the exception, not the rule. It is best utilized for especially complex projects, projects that require extraordinary, early interaction between owner, designer, contractor, and stakeholders, or projects of an emergency nature. As noted above, MaineDOT has used CM/GC only three times in the last 10 years, yet we have delivered about 2,500 capital projects using the traditional design-bid-build project delivery method during the same period.
Looking forward on the Sarah Mildred Long project, final design details and actual contract costs will be determined in late 2014, after the design is finalized, a decision on the TIGER grant application is received, and a construction phase price is determined through continued negotiations or through a bid process.
We at MaineDOT are excited about this project and are anxious to deliver a quality, cost-effective and innovative bridge to our customers.