This Executive Update features news and updated guidance from WAPA as well as dates for the 2021 Annual Conference and Business Meeting.
Asphalt Parking Lots: A Good Business Decision
WAPA is committed to the growth of asphalt pavement solutions in Wisconsin. As part of this effort, we are focused on promoting the advantages of asphalt parking lots.

More than 90% of parking areas in America are surfaced with asphalt because they are quick to construct, easy to maintain, and cost-effective. Asphalt isn't just more affordable, it's durable as well. All asphalt pavements are flexible and can withstand occasional overloads without serious damage.

You can read more about the benefits of asphalt parking lots in our interactive brochure, Asphalt Parking Lots: A Good Business Decision.
To continue developing and sharing guidance on the topic, we are pleased to announce our updated Asphalt Parking Lot Design Guide for 2021 as well.
This companion to WAPA’s Asphalt Pavement Design Guide focuses on all phases of asphalt parking lot design. The guide is organized into five chapters:

  • Assessment and Planning
  • Subgrade and Drainage
  • Construction
  • Maintenance
  • References

Also included is a comprehensive 61-point Inspection Checklist to help an on-site inspector identify key processes and follow best practices to produce a quality parking lot, and a two-page Guide for New Parking Lot Owners that explains what to expect from a new parking lot, best practices for optimum performance, and maintenance tips.

January 2021 update: This publication updates the 20-Year Design ESALs from 2 million to 1 million (found in Tables 3.1 and 3.2).

Many hours are spent designing aesthetically pleasing parking lots, and great curb appeal starts with an asphalt pavement. A parking lot is an investment in the appearance of your business and in the safety of your customers. Asphalt pavements have no built-in, unsightly cracks, and blend in with and enhance its natural surroundings.

Please feel free to share this information with your colleagues and customers.
Asphalt Pavement Resilience
Resilience is a growing concern in the transportation infrastructure community.

Recent federal guidance encourages states to include resilience in their transportation asset management plans, since increasingly frequent severe weather events and other changes to climatic conditions can affect pavements. Here in Wisconsin, resiliency specifically refers to a community's ability to recover from natural disasters like catastrophic flooding.

When considering road construction options that promote resilience, asphalt pavement is the clear winner. It offers the fastest application in both road construction and repair, allowing miles of pavement to be constructed in a single shift and roadways to be opened to traffic immediately in most cases.

In addition, many asphalt plants are portable and can be situated near the construction site and quickly made fully operational to assist with recovery efforts. Asphalt is also less rigid than other construction options, resulting in greater flexibility and more resistance to cracking when disasters do occur.
The National Asphalt Pavement Association (NAPA) recently hosted an introductory webinar on the topic, identifying the tools agencies can use to incorporate resilience into asphalt pavement design, construction, and maintenance to make necessary repairs quickly.

second resiliency webinar highlighted case studies of successful natural disaster responses for roadway infrastructure in different communities across the country and various environmental conditions.

We recommend these resources to better understand the unexpected challenges and obstacles that should be considered in the production and placement of asphalt pavement following a natural disaster. Asphalt provides many advantages over other materials, and resiliency and sustainability are just two examples of how asphalt provides greater benefit for agencies, taxpayers, and the traveling public.
Plastics in Asphalt
The asphalt industry has a long history of using greenhouse gas-reducing materials, such as reclaimed asphalt pavement, recycled tire rubber, roofing shingles, and more to build more-sustainable roads. Plastics in asphalt pavements are a growing subject of interest among researchers; to reduce waste and environmental harm, thought leaders are developing ideas for reusing waste plastic. Since asphalt is a 100% recyclable material, the asphalt industry has a track record of conservation and our researchers are exploring the potential role plastics could play in asphalt.

NAPA has compiled a variety of resources to help you learn more:
  • A short video (available below)
  • Links to recent reports
  • Research summaries
  • A webinar on the topic

In addition, two short summary documents can also be used for legislators and road owners to discuss the current state of knowledge.

Our goal is to continue delivering a high-quality, engineered product that lasts for years to come.
New and Updated Tack Coat Information
Long-term performance of an asphalt pavement is significantly related to the bond developed between successive pavement layers. To help form that bond, tack coat material is applied between each pavement layer. The development of the bond relies heavily on proper tack coat application.

recent webinar offered at WAPA's annual conference identified the materials available for tack coats, as well as how to recognize and avoid common distresses and problems associated with improper tacking. This presentation also outlines how to differentiate between acceptable and poor tack coats.

There are also two new NAPA publications that provide guidelines for the selection of tack coat emulsion types, application rates, placement, and evaluation to ensure the highest quality:
This quality improvement publication, based on NCHRP Report 712, provides a convenient overview of guidelines and best practices for the selection, application rate, placement, and evaluation of emulsion tack coats. New non-tracking tack and polymer-modified emulsions are also covered. This newly updated document also includes the Methods for Addressing Tack Tracking addendum from research conducted by the National Center for Asphalt Technology.
Tracking of tack coat materials can be a major problem from a performance, safety, and aesthetics perspective. If it is a recurring problem with an agency or contractor, it needs to be addressed. This new five-page pamphlet provides general guidance that an agency can consider when addressing issues related to tack tracking on both a statewide and project level.

There are a number of reference materials available concerning tack coat best practices, but if you have any questions or need any information please don't hesitate to contact us.
2021 Conference - Save the Date!
Please save the date for our 2021 conference:

WAPA's 62nd Annual Conference and Business Meeting
November 30 - December 1, 2021
Kalahari Resort
Wisconsin Dells

Please look for more details on our website, in our newsletters, and by email later this year.

As always, please let me know if you have any questions or if WAPA can be of service. As winter turns to spring, we wish everyone a safe and successful paving season.