A section of Chicahauk Trail that was repaved just 10 years ago is already showing “alligator cracking,” civil engineer Joe Anlauf told the Town’s capital infrastructure improvement committee last Wednesday, dropping a bombshell at the end of a lengthy meeting about the latest street projects.
“We’re starting to see failures in asphalt,” Mr. Anlauf said, referring to the 10-year-old pavement of Chicahauk Trail west of the street’s intersection with Trinitie Trail.
It is fortunate for taxpayers that newly elected Town Councilman Matt Neal, a builder with strong analytical skills, will be replacing Mayor Tom Bennett as a co-chairperson of the Capital Infrastructure Improvement Planning (CIIP) Committee. Mr. Neal is well-qualified to deal with determining why roads are failing and addressing stormwater problems, which also came up at the committee meeting.
Interim Town Manager Wes Haskett announced Mr. Neal’s appointment, as well as current committee Co-Chair/Councilman Jim Conners’s reappointment, effective in 2020.
(Please note: The Beacon will publish a report on the cut-through traffic committee’s meeting last week tomorrow.)
“Alligator” or “crocodile” cracking is so-named because the cracks resemble the scales on an alligator’s back. They are longitudinal cracks that become connected by transverse cracks, creating a geometric pattern that looks like reptilian scales.
Also known, perhaps misleadingly, as “fatigue” cracking, such asphalt concrete breakdown occurs when the pavement is carrying a traffic load that the supporting structure cannot hold up, The Beacon has learned in independent research.
Mr. Anlauf, who is referred to as the Town Engineer even though the Town’s contract is not with his engineering company, attributed the cracking to a change in the asphalt mix standard “mandated” by the U.S. government.
In the late 1990s to early 2000s, he explained to the five members of the seven-member CIIP Committee who attended the meeting, the U.S. government “switched” from the “Marshall Mix,” which produced “very sturdy asphalt,” he said, to the “Superpave” system, which is “prone to cracking and fracturing.”
The Marshall asphalt-mix design method, The Beacon has learned, was developed around 1939 by Bruce Marshall of the Mississippi Highway Dept. and later refined by the U.S. Army. For the engineers in our readership, we will note that, according to a Maryland asphalt company, the Marshall method “seeks to select the asphalt binder content at a desired density that satisfies minimum stability and range of flow values.” We will not attempt to translate that for the non-engineers.
The N.C. Department of Transportation (NCDOT) has adopted Superpave, as have the vast majority of other state transportation departments.
Southern Shores’ original roads, which were built without a base, lasted 35 to 40 years or more. Those that have been repaved using the much-studied Superpave system—which came out of a research program established by Congress in 1987 to improve the performance and durability of the nation’s highways—may have to be redone, or significantly repaired, after just 10 years, Mr. Anlauf suggested.
Committee Co-Chairs Bennett and Conners, along with three committee members appointed by the Town Council, greeted this distressing financial news with calm acceptance. No one asked Mr. Anlauf any questions.
The Beacon begs to differ. We may not be road engineers, but we recognize an absurd proposition when we hear one. The question that immediately came to our minds was: What did the Town Engineer and the asphalt design contractor do wrong?
The Superpave system has been in use nationwide for 20 years. If its application were creating roads that deteriorate after just 10 years, the federal government undoubtedly would know and would have taken corrective action.
THE SUPERPAVE SYSTEM
At the risk of losing all readers except those with engineering credentials, we delve into some Superpave history.
The purpose of the $150 million Strategic Highway Research Program (SHRP), which Congress established in 1987, was to find a way to build better-performing and longer-lasting roads.
In 1991, Congress authorized the Federal Highway Administration, an agency within the U.S. Dept. of Transportation, to initiate full-scale implementation of Superpave and other SHRP research results. After 10 years of testing, studying early failures, and making recommendations for revisions, the FHA issued its “Superpave Mixture Design Guide” at:
You may access the NCDOT’s “Quality Management System Asphalt Manual,” which includes Superpave and was published in 2016, at https://connect.ncdot.gov/resources/Materials/Materials/2016%20QMS%20Asphalt%20Manual.pdf.
Superpave stands for Superior Performing Asphalt Pavement System. It includes, according to HMA Contracting Corp., an asphalt paving contractor in upstate New York, “a performance-based asphalt binder specification, a mix design analysis system, many new test procedures, and new equipment.” It is not a product, but rather a process.
“HMA,” The Beacon has learned, stands for hot-mix asphalt. Superpave changed the design methods and procedures for HMA. Most important for the Town’s purposes, the Superpave mix design method takes into account traffic loading and environmental conditions—but only if the HMA contractor knows what it’s doing.
To use the Superpave system effectively, the asphalt technician or contractor has to be able to assess accurately the type and amount of traffic to which a pavement will be subjected, as well as the specific environmental conditions—including high and low temperatures—that the pavement will be expected to perform under.
In other words, engineers and road contractors have to adjust the Superpave system for their geographic areas.
Asphalt is a petroleum-based glue or “binder” that mixes with hard aggregate particles, such as sand, gravel, or crushed stone, to create asphalt concrete. According to HMA Contracting, the Superpave mix design method consists of seven steps, the first two of which are aggregate selection and asphalt binder selection.
Just in doing some cursory research online about the Superpave system, The Beacon easily could see how error or lack of skill or knowledge on the part of a contractor could result in an inferior pavement product.
The members of the CIIP Committee and Mr. Haskett must investigate how town contractors achieved such poor results with the Superpave system. There must be oversight and accountability. They can start with contacting the NCDOT, which approves all road projects.
The Beacon also asks: What has been the experience of engineers rebuilding roads in nearby beach towns?
TOWN’S ENGINEERING CONTRACT
The Town’s engineering contract is with Deel Engineering, PLLC, which works with Anlauf Engineering, PLLC, as a subcontracting “project partner” on all Southern Shores street projects. Typically at CIIP meetings, Mr. Anlauf leads the discussion, as he did last week, and Andy Deel sits beside him.
The Town had a three-year contract with Deel Engineering, which expired June 30, 2019. At its June 4 meeting, the Town Council, pursuant to a motion by Councilman Conners, extended Deel’s contract for one year. The motion passed 3-2, with a strong dissent by former Councilmen Gary McDonald and Fred Newberry, who thought the contract should go through a bidding process.
Even former Councilman Christopher Nason, who voted with the Bennett-Conners bloc, thought that other qualified engineering firms should be considered. But former Town Manager Peter Rascoe did not offer the Council any alternatives—nor did the Council ask for them in a timely fashion—and the Deel contract was set to expire in 26 days. Because he did not consider it acceptable for the Town to be without an engineering contract, Mr. Newberry felt compromised.
Ironically, the contract extension was not signed by the Town until Aug. 20, when Acting Town Manager Haskett signed it. Deel’s president did not sign until Aug. 30. So much for urgency.
The Beacon trusts that the new Town Council will not let consideration of the Town’s engineering contract go until June and will start the process of considering other firms a few months ahead. Mr. Haskett should help in this effort, as well.
UPDATE ON SOUTH AND EAST DOGWOOD, HILLCREST DRIVE, DEWBERRY LANE, AND OTHER STREET PROJECTS
The Town Council has prioritized capital infrastructure improvements projects, ranking them in descending order, with the top four being:
- East Dogwood Trail, from Duck Road (N.C. Hwy. 12) east to Ocean Boulevard
- Hillcrest Drive, from its intersection with Hickory Trail to the SSCA tennis courts
- Sea Oats Trail, from 11th Avenue north to Duck Road
- Dewberry Lane
By previous agreement, the Council has decided to appropriate for the annual capital improvements budget five cents out of every 22 cents per $100 of property value—which is the current tax rate—that the Town collects in real-estate taxes. In FY 2019-20, that amount is $662,340.
According to Mr. Anlauf, the FY 2019-20 budget will not cover all four priority projects. It may take two budget cycles to complete them, he said.
Former Councilman Gary McDonald tried for years to increase the capital improvements budget by changing the tax calculation, but the three-person majority blocked him. Newly elected Councilwoman/Mayor Pro Tem Elizabeth Morey—a more appealing messenger, apparently—may have better luck.
During a public-comment period, she suggested undertaking the “useful exercise” of looking at how many miles of the Town’s 37.6 miles of roadway have been rebuilt, over how much time, and then computing: “How long will it take at the rate we’re going to get to the end?”
The answer to this question, Ms. Morey said, might lead the Town Council to “consider that the annual budget is insufficient.”
This idea, she said, had been suggested to her by CIIP Committee member Glenn Riggin.
Mr. Anlauf is to do this calculation and present his result at the next CIIP Committee, which will likely be in February.
Updating what is going on now:
SOUTH DOGWOOD TRAIL SIDEWALK: As The Beacon reported 12/18/19, Mr. Anlauf informed the CIIP Committee that the tree and stump removal on the east side of South Dogwood Trail has been done, and that “no additional tree removal is to occur.”
Pink flags currently attached to trees and bushes, which have raised concerns for property owners, mark “sensitive areas,” Mr. Anlauf explained, not future removals.
The suggestion by Mr. Anlauf that some flags may designate where tree roots may be located raise a red flag for The Beacon. Damage to roots may result in tree deaths, a concern we red-flagged before the Town Council when we argued that the Town Engineer may have underestimated the number of trees that will be lost.
The Beacon advises all South Dogwood Trail homeowners to keep an eye on the pink flags to ensure that no further tree removal occurs.
Also, as earlier reported, the sidewalk construction is to start after Jan. 1 and will occur along the entire route, with work taking place at multiple locations. Crews will work first on the “easier sections with minimal grading,” according to Mr. Anlauf.
DEWBERRY LANE: Although it is fourth in priority, the CIIP Committee spent considerable time discussing design possibilities for Dewberry Lane, a 230-linear-foot-long lane off of Bayberry Trail. There are only three houses fronting on Dewberry, which ends in a Y, branching off to the driveways of two of the houses.
According to the Town’s “Guiding Standards for Use in Engineer Design of Necessary Street Rebuilds,” which were adopted in 2014, cul-de-sacs or other NCDOT-recognized turn-around areas must be installed in all locations where the roadway has no outlet, in order to “facilitate the maneuvering” of fire trucks and other emergency vehicles.
Mr. Anlauf sought an amendment to the standards for Dewberry Lane because “they are going to be difficult to adhere to.”
Constructing a cul-de-sac on Dewberry—one look at this picturesque lane reveals this suggestion to be ludicrous—“calls for a lot of removal of trees,” Mr. Anlauf said, but he said he felt he had no choice but to do so, under the standards.
Mr. Anlauf presented as an alternative to a cul-de-sac a “hammerhead turn-around,” which essentially is a fire-access driveway that serves no more than two dwellings. It would use the Y-configuration that is already in place.
Not only is Dewberry Lane unique because of its length, it has unique stormwater mitigation issues because of runoff from Bayberry Trail. Existing stormwater infrastructure is already quite extensive.
Mayor Bennett led the committee’s critique of the engineer’s Dewberry Lane rebuild design plans, showing both practicality and a concern for aesthetics. He pointed out that the standards allow the Town to investigate “other design options” in “locations where adequate area [for a cul-de-sac] is not available” and the “need for a larger turn-around area is necessary.” (Standard 5)
The Beacon would dispute the need for a larger turn-around area on Dewberry Lane, but we certainly welcome the Mayor’s flexibility.
By consensus, the committee agreed with the Mayor’s directive to Mr. Anlauf to proceed with the hammerhead turn-around and to get the “maximum” stormwater mitigation he can manage while removing a “minimum” number of trees.
“Do the best you can do with it,” Mayor Bennett said. “. . . give people something they’re reasonably comfortable with.”
EAST DOGWOOD TRAIL: According to Mr. Anlauf, the contract for stormwater and other improvements on East Dogwood Trail, between Duck Road and Ocean Boulevard, “went out to bid” last Tuesday, with bids scheduled to be opened Jan. 23.
The contractor should start work two weeks after that, he said. The contract completion date is May 1, but this “may be pushing it.”
HILLCREST DRIVE (the cut-through route portion): The survey work on this 3700-linear-foot-plus-long section of Hillcrest Drive is done, said Mr. Anlauf, who further reported that he would start the design work after Jan. 1.
The Town Engineer anticipates that the job will be bid upon this spring, and the work will occur during the summer, which would disrupt the heavy weekend cut-through traffic—sending it to Sea Oats Trail and Wax Myrtle, off of Hickory Trail, if the Town takes no action to prevent it.
Much of the discussion that the CIIP Committee had with Mr. Anlauf about the Hillcrest Drive rebuild concerned the width of the new street. The engineer reported that its width currently varies between 16 and 20 feet, except at the top of the hill, in an area that we called in 1972 “Lookout Point.”
You could park on the roadside at Lookout Point and view the Currituck Sound and the ocean simultaneously. Unfortunately, tree growth has eliminated this glorious panorama.
Mayor Bennett suggested that, in the interest of public safety, Hillcrest Drive be 20-feet-wide, except at Lookout Point, where he thought 22 or 24 feet would be more appropriate.
“If you narrow [Lookout Point] too much, you’ll endanger the public,” he said, noting that many people walk and bike on Hillcrest Drive.
Mr. Riggin brought up the possibility of a sidewalk down Hillcrest Drive that would originate at East Dogwood Trail. If a sidewalk were to be constructed, he observed, the road should be 18-feet-wide.
Mr. Conners, who said he was “told not to bring up” a town-wide walking system, which he endorses, suggested that the committee keep “focused” on the roadway and not anticipate a sidewalk.
SEA OATS TRAIL: The survey work on Sea Oats Trail has not been done yet.
*Committee member Al Ewerling pointed out that the Juniper Trail Bridge is “bouncing more,” as the “road is sinking more.” No action was taken.
*The Mayor suggested widening the eastbound lanes on East Dogwood Trail at the Hwy. 12 traffic light in order to reduce the tightness of the right turn. He suggested obtaining a foot or two from the median to the north of the lanes and asked if this work could be incorporated into the East Dogwood Trail project contract. Mr. Anlauf advised that such a change would cost about $2400 and could be put into the East Dogwood project “by addendum.”
*Mr. Haskett brought up stormwater problems that affect several homeowners around 245 Sea Oats Trail. Committee members are aware of this flooding, as well as stormwater problems elsewhere in Town—some of it caused by street improvements, such as curbing—and suggested that when Councilman Neal comes on board, a comprehensive approach to such problems should be devised. No action was taken otherwise.
Ann G. Sjoerdsma, 12/21/19