Road and Bridge Standards

New state mandates trigger assessments of costs and benefits.

This piece originally appeared in The Vermont Standard.

This past January, the Vermont Agencies of Transportation (VTrans) and Natural Resources (ANR) approved revised recommended minimum Town Road and Bridge Standards, which municipalities must adopt to be eligible for financial incentives available under certain grant programs. Some local cities and towns have already endorsed the amended standards, others are still weighing their relative costs and benefits.

The standards primarily address factors that impact drainage along roadways, through culverts, and under bridges. They were first developed in 1999 in response to concerns by the Federal Emergency Management Agency (FEMA) and others about damage caused by heavy storms.

During the mid- and late-1990s, “we had quite a few events that triggered FEMA declared disasters,” says Tammy Ellis, the VTrans Administrator for District 4, which includes Woodstock, Bridgewater, Hartland, Hartford, and twenty-three other nearby towns, “some of the [flood] damage to roads could have been prevented had mitigating standards been implemented; the same roads were being repaired over and over.”

The original standards required that new gravel roads be constructed with deep sub-bases and that proscribed methods be used to minimize erosion of drainage ditches alongside new roads. They also set minimum diameters for new culverts, which are pipes or ducts used to manage water runoff and to allow roads to pass over streams, and required that construction of large culverts and openings under bridges meet certain specifications. Municipalities that adopted the standards were then eligible for FEMA grants to upgrade to the standard those parts of their drainage infrastructures that were damaged in subsequent declared disasters. The State of Vermont added incentive by upping reimbursement rates in two road construction grant programs for municipalities that adopted the standards.

All of the towns within District 4 endorsed them, says Ellis; so did most of the towns in the state.

Then, in the 2010 session, the State Legislature passed Act 110, River Corridors and Buffers, which in part charged VTrans with revising the Town Road and Bridge Standards, subject to ANR approval, to “address activities which have a potential for causing pollutants to enter the ground water and waters of the state, including stormwater runoff and direct discharges to state waters.” Where the original standards applied to “all future road and bridge construction”, the amended standards, according to the legislation, are for “construction, maintenance, and repair of all existing and future state and town highways.”

VTrans and the ANR issued the revised standards on January 15. The original requirements are largely intact, with some enhancement for more exacting treatment of roadways, ditches, culverts, and guardrails. Requirements were added for reviewing new roadway access requests and for training maintenance crews.

The revised standards do not present a problem for Woodstock Village, says Municipal Manger Phil Swanson, because its roads are mostly flat and are served by an in-place storm drainage system. The provisions that deal with roadside ditches do present a challenge for the Town of Woodstock, though. The basic requirements for treatment of the ditches are largely unchanged: channels along shallowly sloped roads must be mulched and seeded, those along moderately pitched slopes must be matted and seeded, and ditches adjacent to the steepest roads must be lined with stone.

However, “there’s a rub,” says Swanson, referring to the new requirement to upgrade existing ditches during repair and maintenance. “If you have a grade less than 2%, you throw some grass seed on it, no problem,” he says, but lining existing steep ditches with stone can be expensive, and the costs are exacerbated by an additional requirement to create flat-bottomed, u-shaped channels. That means, says Swanson, “you go out with a bucket loader.” And, he adds, “it’s not something you do once and walk away from.” The stone-lined ditches catch the fine sand and gravel that wash off the road, that’s what they are supposed to do, but eventually the stones become clogged with the “fines” and stop working. Then the ditches have to be cleared out and the stones somehow cleaned or replaced. Swanson estimates that of the 70 miles of town-maintained roads, about 50 exceed the 5% slope threshold that triggers the most stringent requirement. All 50 miles would not have to be upgraded at once, says Swanson, but if, for example, if “you go out with the grader, and the grader roughs up the ditch,” the Town would then have to reshape the ditch and line it with stone to be in compliance.

The Town recognizes the adverse impact of sediments washing into its rivers but approaches the problem in another way.

“We are trying to be good stewards of our waterways,” says Swanson, “it’s just that we are going about it differently.”

To prevent damaging runoff, the Town cuts many smaller, perpendicular troughs along steep ditches, and these channel water off into forests and fields. “We get the water off the road before it generates the big velocities that eat up roads and ditches and put bad sediments into waterways,” he adds.

The Woodstock Town Select Board was scheduled to discuss the revised Town Road and Bridge Standards at their April 5 meeting.

In Hartland, the Board of Selectmen have asked Town Manager Bob Stacey to seek clarification of a new provision that requires a hydraulic engineering study for replacement or construction of any culvert with a drainage area that exceeds a quarter of a square mile. Studies are performed gratis by state engineers, “you submit a request and they will get to you,” says Stacey, but he feels that findings are often geared to worst-case scenarios. Hartland is considering replacing a Jenneville Road culvert, for example, that currently has a 3 by 4 foot opening. “We had a study done on it, and they want us to go to a 5 by 12 foot opening,” he says, “between something that’s 12 square feet versus 60 square feet, we’re talking $50-60,000 for replacement.”

Stacey feels, though, that Hartland will likely adopt the revised standards, despite the “sticky wicket” of the culvert requirements.

“I applaud what the state is trying to do and why they are trying to do it,” he adds.

Municipalities that adopt the new standards, or alternatively certify that their own standards exceed the new requirements, receive an extra 10% state reimbursement on projects approved for grants under the Town Highway Structures and Class 2 Roadway programs. That’s not necessarily a compelling incentive, however. Those pots of money are relatively modest, and only periodically available to a particular town.

“Not every town gets a grant every year,” says District Administrator Ellis. The state has a project prioritzation system, she says, that uses a town’s relative total mileage in the district and the share of grant money it has received in the past to determine eligibility for funds under those programs in any given year. So the 10% incentive may mean at most several thousand dollars to a municipality every few years.

The Town of Woodstock does hope to apply this year for a Class 2 Roads grant to pave a one-mile stretch of Pomfret Road. So, if the Select Board declines to endorse the revised Town Road and Bridge Standards, they may miss out on about $9-10,000 in reimbursements. Municipal Manager Swanson says the Board will have to weigh the cost of and options for compliance against potential for those incentive reimbursements.