Category: Design

From Groundbreaking to Ribbon Cutting: An Internship with Hoyle, Tanner

Over the past three months, I have had the pleasure of being part of the Hoyle, Tanner team, primarily in the Bridges & Structures group. I have gotten to see and experience a variety of different projects at all stages, and I am grateful for this opportunity and everything I learned along the way.

Projects in Derry

The first half of my internship experience was spent in Derry, New Hampshire replacing a bridge with structurally deficient culverts on this box culvert project. Here I performed Resident Project Representative (RPR) services and observed construction from start to finish – when the excavator broke ground to when the bridge was reopened to traffic. It was very rewarding to see the full project life-cycle and be there to walk the bridge. Every day in the field there was a new step and process for me to learn and see for the first time. Being on site opened my eyes to how many people are involved in the entirety of a project. Now I better understand the client, contractor, and engineer’s roles in making a project successful. For example, Hoyle, Tanner, the contractor, and the Town worked together to make field changes as needed.

Working on this project also introduced me to new engineering computer programs such as Bluebeam, MicroStation, and Mathcad that allowed me to edit drawings, review check sets and create other engineering documents. User efficiency greatly improved from the first days of using a program compared to after a couple of months.

Projects in Bedford

The last half of my internship has been spent in Bedford, New Hampshire where I took on day-to-day inspections of a gas main project. My duty there was to make sure the trench is properly backfilled and compacted and make sure everything goes according to plan. This role was rewarding because it allowed me to work more independently. I frequently communicated with the client on day-to-day progress and was the bridge of communication to the site.

At Hoyle, Tanner I was welcomed with open arms (virtually) and felt like I belonged. I am thankful my supervisor emphasized spending as much time in the field as I could because the experience taught me valuable lessons. I enjoyed the team environment and how my questions were encouraged by everyone. This opportunity brought me new experience and knowledge, and has increased my interest in field work. I’d like to personally thank Matthew Low, PE for providing me with this opportunity, Josif Bicja, PE for showing me what it takes to be a great engineer, and Katie Welch, EIT for guiding me along the way.

Derry, NH Box Culvert Replacement Project

A New Technology for Covered Bridge Inspections

Drone image of Kingsley Covered Bridge

The Unsung Beauty of Covered Bridges

Covered bridges, to me, were the quintessential structures of the 19th century, and to this day, can still inspire awe. These are bridges that were often built from trees cut locally, hand-hewn, brought to the site by livestock and assembled without modern machinery. When completed, you have a sort of house of cards; a wooden plank deck spanning a stream or raging river, walls reaching up from its sides containing many vertical and diagonal wooden members, a roof covering the expanse containing even more diagonal members, all held together with mortise and tenon joints and wooden pegs. This is a mongrel of bridge construction that has a beauty to it like no other, blending in with its surroundings as if it were always there, the backdrop for postcards, calendars and many personal moments shared between friends and loved ones. Sadly, most of these bridges have gone into the pages of history – neglected beyond repair, victims of mother nature, casualties of vandals, replaced with modern structures or simply forgotten. Those that still exist are revered and protected passionately by those who still believe in their relevance and their beauty. They do however require regular inspections and maintenance to ensure they can meet the needs of the communities they serve.

Those that still exist are revered and protected passionately by those who still believe in their relevance and their beauty. They do however require regular inspections and maintenance to ensure they can meet the needs of the communities they serve.

Inspections are Challenging for these Structures

Over the years, I have had the awesome opportunity to inspect many of these beautiful works of craftsmanship. These inspections are laborious in nature, requiring multiple days for a thorough inspection, getting covered in dirt and dust from crawling around the hard-to-reach spaces. It’s vital to know the size and condition of as many members as can be seen and reached, recording all that is found – dimensional losses, an array of structural deficiencies including but not limited to cracks, splits, checks, insect infestation and rot to name a few. The tape measure, extension ladder, headlamp and digital camera are tools of the trade. But what about inspecting the places that are more difficult or impossible to get to because of the length and height of these structures or the geography they span?  Simply put, you get what you can, as good as you can, and the rest is filled in with existing plans and many, many digital photos. The camera is your best friend when inspecting and is an invaluable resource. But even so, photos can be deceiving – awkward angles, poor lighting and size distortion, cause confusion as to what is truly being captured. As for inspecting floor systems, getting underneath is the only way to go, either by rigging, rope climbing or even by boat if the height above the water makes it feasible.

When the Standard Inspection Options Aren’t Adequate

Recently I traveled to Clarendon, Vermont with Josif Bicja, PE to inspect the Kingsley Covered Bridge for a scoping report to determine the feasibility of multiple rehabilitation options. This is an historic 119-foot-long, single span, town lattice bridge spanning the Mill River flowing 35 feet below. The Kingsley Covered Bridge poses the same issues as any other covered bridge inspection, but in addition, because of the height above the stream, it makes it difficult if not impossible to get a good visual of the floor system and siding. A rigging company could have been hired to provide access to inspect the floor system through the use of bridge trackers or bucket boats which will get you up close to get that good visual, or the bridge could have been climbed, but these options are not economically feasible for a scoping study. The options you are left with is to don a pair of waders, carefully walk out into the water with your clipboard and camera and capture what you can. If the water is not passable, you stand on the shore and do your best to get the information you need.

There is a better way. The drone. Those sci-fi looking machines, with their distinguishable propeller sound that are used widely in law enforcement, the military and with private enthusiasts alike, have been making their way into other useful applications. Over the past few years, engineering companies like Hoyle, Tanner have seen the value of drones for public relations documents, project marketing, 3D visualizations, traffic studies, and now bridge inspections. The height of this bridge over the Mill River made it a perfect candidate to fly a drone and test its capabilities in this capacity. Drones have safety features that will not allow them to fly close to aerial obstructions, like trees and overhead utilities, or fly in strong winds such as updrafts under a bridge, which are both prevalent at this site. The safety features would have to be turned off for the drone to perform its inspection well, which meant that the steady hand of an experienced pilot would be essential.

For the underside of the bridge, it flew a few feet from the structure providing the ability to clearly see the members that make up the floor framing, including joint locations and condition. Then the drone was flown along the sides of the bridge and along the roofline, capturing a similar up-close visual of the vertical siding and metal roof conditions that we normally would not have been able to see.

Patrick Sharrow, AAE from our Burlington, Vermont office drove down and met us on-site on the morning of our second day inspecting the bridge. It took Patrick just a few moments to familiarize himself with the structure and geography of the site, understand what we needed the drone to capture and determine the best launching spots for the drone. Looking at the handheld monitor, Josif was able to give instructions as to where he needed the drone to fly,  while I acted as spotter to make sure the drone kept a safe distance from any aerial obstructions and Patrick executed the flight. For the underside of the bridge, it flew a few feet from the structure providing the ability to clearly see the members that make up the floor framing, including joint locations and condition. Then the drone was flown along the sides of the bridge and along the roofline, capturing a similar up-close visual of the vertical siding and metal roof conditions that we normally would not have been able to see. The videos captured of these hard-to-get-to portions of this bridge will allow for better recommendations for the multiple rehabilitation options, leading to more accurate costs for the client. We then took the drone to a higher elevation and flew a few hundred feet upstream down towards the bridge, giving a bird’s eye view of Mill Stream. Patrick flew it at different elevations and angles capturing fantastic footage of the morphology of the stream and a greater scope of how this bridge is situated on the site. Portions of these videos could be used in public information meetings to help educate the public and as tools for Hoyle, Tanner.

Day-to-Day Needs of the Community Combined with Aesthetic Nostalgia

In less than an hour, we were able to gather more information about this structure than we would have been able to because of the site restrictions this bridge poses. The best part is that all players in the game benefit from this. The design team will have the ability to make more accurate rehabilitation recommendations. The client will have the advantage of receiving more accurate cost estimates for each rehabilitation option. The public will receive the best rehabilitated structure option, marrying together the day-to-day needs of the community and the aesthetic nostalgia it provides to all.

At-The-Ready Consultant Services: A Streamlined Approach to Starting Your Project

If your community was awarded a grant through the Vermont Agency of Transportation (VTrans) Municipal Assistance Bureau (MAB), you can take advantage of a streamlined approach to procuring your project consultant through the At-The-Ready (ATR) process. With this choice, municipalities have an alternative option to the standard RFQ/RFP process; an option that can speed up your proposed project schedule using prequalified and reputable experts in their field with success in delivering projects in accordance with VTrans MAB standards. VTrans maintains ATR consultants from a qualified roster, ready for qualifications-based-selection (QBS) when a project arises.

This accelerated procurement method can be applied to three categories of work:

  1. Design (including Scoping)
  2. Municipal Project Management
  3. Construction Inspection

If the ATR process is something your community would like to consider, VTrans has set up a simple Guide and Flowchart that can be followed and coordinated with your VTrans Project Supervisor. Begin by defining a selection committee (minimum of two members); along with the Municipal Representative in Responsible Charge (typical members could include the Municipal Project Manager, Public Works Engineer, Road Foreman or other municipal representatives). The committee then reviews a minimum of three consultant qualifications packages and selects the firm that best meets the needs of the municipality for the particular project. Once the committee chooses a firm, they can work through the cost proposal process with the VTrans Project Supervisor and the consultant.

For a municipality, the ATR process is beneficial for more than just accelerating the procurement of consultant services. Utilizing ATR also ensures you will be selecting from qualified firms that are experts in completing MAB funded projects. Instead of preparing a laborious Request for Qualifications package and then reviewing multiple submissions, the QBS selection is made easier, giving the option of only a minimum of three to pick from, while maintaining full state and federal grant/funding eligibility.

Hoyle, Tanner has had a working relationship with the VTrans MAB group for over 20 years and has been an ATR Consultant under the Design Category since the program began in 2017. We are a prequalified Design Consultant and are At-the-Ready whenever a municipality needs.

If you have any questions about the ATR process, contact Jon Olin, PE, our Vice President and Regional Business Manager of our Vermont office.

What you May not Have Considered about Solar Energy in New England

Hoyle, Tanner is currently providing professional engineering design services for the development of solar energy in New England. We are working for several solar companies as the solar industry has not only taken off in the flatlands of our Midwest United States, but solar energy development is also happening in our New England backyards.

There are many reasons why this industry has recently become so popular. Solar energy has become a viable option because of the sun’s power – but also because of its cost. As the technology of solar energy has become more efficient, the option for purchasing solar power has become a reality to an average energy user.

In order to consider solar options, permitting and procurement need to be considered.

Permitting

Public utilities commissions and state regulators have recently developed and revised rules and regulations for the advancement of solar energy. Hoyle, Tanner has stayed up-to-date with the development of these guidelines so that we can keep our clients educated and able to make sound decisions and reliable investments — not only based on costs, but also permitting success. The probability of getting a project permitted is a major milestone in the progression of a project, and can in many cases can determine if the project ever gets started.

There are many factors that contribute to the permitting and design of a solar array. Following is a list of some major factors that can affect development:

  • What is the size and shape of the property?
  • Is the property located in a properly zoned area or can it be rezoned?
  • Are the soils adequate to develop for this use? Are there significant wetlands? Are they well drained soils?
  • Is the topography adequate for solar development? Is the orientation of the property favorable for solar development?
  • Are there abutting structures on neighboring property that would prevent sunlight from reaching the site?
  • Is there adequate access to the property?
  • Is there access to an existing power source to transmit the power?
  • Are there natural resource protection areas within the site (vernal pools, deer wintering areas, or historic preservation areas)?
  • Does the developer have adequate title to the property?

Hoyle, Tanner has developed several solar array sites being cognizant of all the factors pertaining to a successfully designed and permitted project, while keeping versed of the regulatory processes. With our experience, we can save the client time and money while helping them realize a successful project.

Procurement

In many state governments, there is a procurement process for renewable energy projects (that are part of energy packages). These packages contain guidelines for the development of a limited amount of energy. What we are finding in some states is the need to increase the development limits as demand increases. Hoyle, Tanner is working with state agencies to make sure we are aware of these opportunities so that we may share them with our clients.

In some states there is a procurement process, raising the net metering cap, allowing arrays of up to 5MW — 5,000 KW — to sell or store excess energy. 

Raising the cap is what makes renewable energy development viable for investors, developers, and municipalities. These opportunities to create renewable energy not only lower the states’ dependence on fossil fuels to generate electricity but are also expected to create new jobs in the coming years as the number of projects increase.

Many states look to increase their renewable energy portfolio standard — the amount of renewable electricity created as opposed to that created by fossil fuels — from lows currently at 10% or less to 40% or 80% by 2030 and some even at 100% by 2050.

Helping Developers

We understand the importance of this type of development and the need for development of renewable resources. Our design experience helps the developers understand the limitations of development and of course the permitting process.

Hoyle, Tanner’s experts are here to help. If you have any solar development questions, contact Andy Sturgeon, Vice President and Regional Business Manager.

Landslides: Prevention & Repair Through Slope Stabilization

Slope failure photo with blog title

In New England, March marks the last weeks of winter and the start of spring rains and snow melt.  Paying attention to erosion control during this time of year is always on the minds of municipal public works staff, state agencies, construction companies, and even homeowners, especially those fortunate enough (or perhaps not) to have water frontage. 

A 2018 study conducted by the USDA found that precipitation is increasing in the northeast more than any other region in the United States. The frequency of consecutive wet days is generally increasing in the northeast and precipitation extremes have also become more frequent. Given these trends, it is no surprise that peak flows in rivers and streams are also increasing and occurring earlier in the year which can result in a greater risk of flooding.

While it is difficult to prevent major erosion of stream and river banks due to extreme precipitation events, damage can be mitigated by inspections of at-risk areas combined with prioritization of these areas for repair. It is important to address slope failures quickly because bank degradation can cause significant damage including loss of property and infrastructure, sedimentation of the waterbody, water quality issues and damage to critical riparian buffer areas. As civil engineers, we can provide assistance with erosion control issues that range from preventative design practices, culvert replacements and stabilization of failed embankments.

Below is a list of some stabilization practices along with before and after photos of our recent embankment stabilization projects.

One such embankment failure occurred in Lancaster, New Hampshire, when high flow conditions in the Connecticut River resulted in severe washouts along an 800 foot long embankment causing loss of land and unstable soil conditions. Hoyle, Tanner designed and permitted solutions to repair and stabilize the slope using native riparian vegetation and rip rap armament. Live willow and dogwood stakes were planted in soil between the rip rap stones.

Terms to know:

  • Live willow & dogwood stakes: Living shrub cuttings that take root quickly in bank environments – provides natural habitat and additional erosion control
  • Rip rap: Large stones used for protection and dissipation of energy from high water flows
Washout along the Connecticut River in Lancaster
Lancaster Embankment after Stabilization

Hoyle, Tanner also designed and permitted repairs to a steep slope in Rochester, Vermont, when intense rainfall events undermined the toe of the bank, causing the slope and roadway above to fail and slide into Brandon Brook 90 feet below.  The repair solutions included installation of a blast rock toe detail and stone facing with grubbing material along the hillside to restore the slope. The roadway was reconstructed and a mid-slope underdrain was installed to intercept groundwater seepage. Debris from the slope failure was removed from Brandon Brook and the streambed was restored.

Terms to know:

  • Stone facing with grubbings: Combination of stone and native material to promote vegetation growth
  • Blast rock toe: Large rocks placed at the toe of the re-stabilized slope to combat undermining
Rochester Slope Failure at Brandon Brook
Brandon Brook Stabilized Slope Repair

Improving safety and combatting damage from growing peak flows and extreme storm events is an important part of our job. Hoyle, Tanner is excited to offer solutions to slope stability issues and challenging site conditions. For more information on how we can be of assistance, please contact me.

New Changes for Designing Low-Volume Roads

While staying up-to-date on standards, manuals, guidelines, policies, and specifications can be challenging, the Hoyle, Tanner design teams have welcomed the Second Edition Guidelines for Geometric Design of Low-Volume Roads (Guidelines) recently published by the American Association of State Highway and Transportation Officials (AASHTO). The updated guidelines expand the definition of low-volume which provides greater flexibility to Hoyle, Tanner’s engineers to design the appropriate solution for the challenges our clients face. We’re going to cover some basics of the Guidelines and why it is so welcomed.

In the first edition (2001), low-volume roads were considered to have traffic volumes of 400 vehicles per day (vpd) or less. With the newest release (2019), the Guidelines expand coverage to roads with traffic volumes of 2,000 vpd or less. What does 400 vpd look like? For perspective: If you were to walk down a street, you’d expect to see one vehicle approximately every 3 ½ minutes at 400 vpd. If the same road experienced 2,000 vpd, you’d expect to see one vehicle approximately every 45 seconds.

According to the Guidelines, 80% of the roads in the U.S. are low-volume roads.

To determine if that 80% was applicable to our clients, we reviewed available traffic counts for an “average” New Hampshire town and found a conservative 70% of their road miles met the new definition of low-volume.

The Guidelines still remain focused on very low-volume roads (≤ 400 vpd) but the inclusion of roads with volumes of ≤ 2,000 vpd is greeted with open arms. This provides our design teams an additional resource on more projects; before the latest release we could not use the Guidelines on most of our projects as traffic volumes typically exceeded 400 vpd. However, a majority of past projects had traffic volumes that did not exceed 2,000 vpd.

What’s the benefit to our clients and designers

quote-from-aashto

The Guidelines apply to both new construction and evaluating existing roadways. Here are a few things designers can consider for the construction of a new low-volume road:

Reduce pavement width allocated to vehicles, narrow the road. The obvious benefit to narrower roads is reduced construction cost. Another benefit is a decrease in environmental impacts. Thinking a little bit further beyond the edge of road, the savings from a narrower road could be invested in pedestrian and bicycle accommodations.

Reduce the design speed, allowing for the use of sharper horizontal curves. This could be used to avoid or minimize impacts to environmentally sensitive areas, an excessive cut, an excessive fill, or negative impacts to abutting properties. Doing any of these could not only reduce construction costs, but also potentially speed up the construction time and reduce the environmental permitting coordination.

Reduce the stopping sight distance, allowing for the use of sharper curves. Similar to reducing the design speed, however, this provides the designer flexibility for both the horizontal and vertical (profile) alignments. This could be used to avoid or minimize impacts to environmentally sensitive areas, an excessive cut, an excessive fill, or negative impacts to abutting properties. Doing any of these could not only reduce construction costs, but also potentially speed up the construction time and reduce the environmental permitting coordination.

Reduce the clear zone, and thus reduce or eliminate guardrail. A little side note, a clear zone is an area that allows a driver to stop safely, or regain control of a vehicle that has left the roadway. Since guardrail is a roadside hazard, costly to install, and costly to maintain when impacted, being able to reduce guardrail or eliminate it reduces construction maintenance costs and potential accidents involving it.

With this increased flexibility the Guidelines provide there is still engineering judgement to be used. For instance, it would be ill-advised to combine a narrow road with sharper curves and reduced stopping sight distance. Remember the intent of the Guideline is to reduce crash frequency and severity while prudently using public funds.

infographic

What about all the existing roads to be maintained?

We have the ability to evaluate how the existing road is performing and if it meets the Guidelines. When something doesn’t meet the Guidelines, that doesn’t mean that it needs to be fixed.

For example, let’s consider a one-mile segment of low-volume rural road in good condition, and we’re looking to resurface it before it becomes worse. We go out to the site, take measurements and notes of existing conditions, and find the following:

  • The average road width is less than the Guideline recommendation.
  • There is a curve that is sharper than the Guidelines minimum radius, has no warning signs, appears multiple vehicles have left the paved surface within the curve but no reported accidents in the last 5 years.
  • There are multiple trees within the clear zone but no signs of impacts or reported accidents.

There are several ways to address each of the issues. Recalling the purpose of the Guidelines is to make improvements at locations where it can be expected to provide substantial crash reduction benefits the design team makes a recommendation. Maintain the existing road width except within the sharp curve, where the pavement is to be widened to the Guideline minimum and the trees within the clear zone are to remain.

Hoyle, Tanner’s transportation design engineers are experts in roadway design, pavement layout, roadway stormwater, and safety for vehicles and pedestrians alike. We research and commit ourselves to learning the newest design guidelines for a safer, healthier community for drivers, roadway designers, and pedestrians. Questions? Call (603) 669-5555 ext. 181 or email me to discuss the latest technology and guidelines in the transportation engineering industry.