WMA, Recycled Materials Use Explodes

A new survey* on the use of recycled materials and warm mix asphalt (WMA) conducted by the National Asphalt Pavement Association (NAPA) (under contract to the Federal Highway Administration) has found that nearly a quarter of all asphalt mixtures produced in the 2012 construction season were made using WMA technologies.

As contractors, I’m sure that’s no surprise as you produce and place these WMA pavements every day. We already know that asphalt is the most recycled material in the U.S. – with more than 99% of asphalt pavement reclaimed from roads going back into new roads.

The explosive growth of WMA in our industry is noteworthy, however. According to NAPA, the 1,141 U.S asphalt plants surveyed produced 86.7 million tons of WMA during the 2012 construction season. That’s a 416% increase in the use of warm mix since the survey was first conducted in 2009.

Asphalt pavements also continue to use increasing amounts of reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) materials. According to the survey:

  • In 2012, RAS usage reached 1.86 million tons — a 56% increase over 2011, and a 165% increase since 2009. Since 2009, RAS usage has been reported in 37 states.
  • RAP usage also continued to climb, increasing to 68.3 million tons in 2012, a nearly 22% increase from 2009; 98% of producers reported using RAP in their mixes.
  • More than 1 million tons of other recycled materials -- ground tire rubber, steel and blast furnace slags, etc. -- were reported as being included in asphalt mixes.

The benefits of using warm mix are numerous: it uses less energy when produced, reduces emissions, improves worker safety, and offers construction benefits. U.S. Secretary of Transportation Anthony Foxx said in January during the 2014 Transportation Research Board Annual Meeting that the use of WMA is expected to save $3.6 billion in energy costs alone by 2020.

In addition to WMA benefits, the amount of RAP and RAS used during the 2012 paving season translates to a savings of 21.2 million barrels of liquid asphalt binder, saving taxpayers some $2.2 billion.

The bottom line – WMA and recycled materials are here to stay, and their usage is only going to increase. And that’s a good thing for all involved.

Thanks for reading!

* The survey was conducted in mid-2013. Results from 213 companies with 1,141 plants in 48 states and Puerto Rico, along with data from 36 State Asphalt Pavement Associations, were used to calculate industry estimates for total tonnage.