Listed below are recent posts across all of CalRecyle's blogs.

  • Why Do We Recycle Tires?

    tire fire

    Tire fires of past decades could take months to extinguish, while emitting smoke thick containing cyanide, carbon monoxide, and other toxins.

    Until 19 years ago, countless illegally dumped tires polluted our state. Large piles of old tires sometimes even caught fire in the hot California sun. These tire fires put off toxic smoke containing cyanide and carbon monoxide. Because a fire can continue to burn deep inside a pile of tires after the top layer appears extinguished, firefighters struggled to put out these smoldering blazes that emitted thick, black plumes of toxic smoke that sometimes burned for months.

    California turned to recycling to solve the problem of tires:

    1. Catching fire
    2. Clogging waterways
    3. Filling with water that bred disease-causing mosquitoes

    tire pile

    Where can we put 51 million tires a year?

    California’s 35 million registered vehicles generate 51 million used tires every year. To manage this constant flow of vulcanized rubber into the waste stream, California passed the Tire Recycling Act in 1989, which created the Tire Recycling Program. After a series of devastating illegal tire pile fires in 1998 and 1999, the law was strengthened in 2000.

    To prevent illegal stockpiles of tires, the state has:

    1. Permitted tire storage facilities
    2. Enforced used tire storage and management laws
    3. Developed recycled tire product options

    To find new uses for more than 82 percent of 51 million worn-out tires a year, CalRecycle constantly innovates and evaluates safety studies. The department awards grants and loans to businesses and public entities to expand the safest markets for waste tires.

    tire cover on playground

    Different styles of playground cover are a common use of recycled tires.

    Across California, companies are producing tire-derived products made from recycled tires, including:

    • Playground surfaces
    • Roofing
    • Flooring, including rubber mats for gyms
    • Path cover
    • Roads
    • Accessibility ramps

    cars driving on golden gate bridge

    Where the rubber becomes the road

    For more than 30 years, ground-up, recycled tires mixed with asphalt have produced cost-effective, durable, and environmentally friendly binder in concrete road cover.  Overall, about 2.7 million tires have gone to paving California’s roads.

    Tire rubber makes up only about 1 percent of rubberized asphalt concrete. The asphalt binder absorbs the rubber into it, reducing its ability to break away as a microparticle. These streets last about 50 percent longer than roads made from asphalt alone.

    tire project

     Many local governments have used tire-derived aggregate in place of conventional construction material for civil engineering projects to:

    • Backfill retaining walls
    • Stabilize hills to keep them from slipping into landslides
    • Absorb vibrations 
    • Fill in land for other reasons

    This tire material helps solve a variety of civil engineering challenges because it drains better and costs less than other lightweight, mixed material building aggregate.

    “Tire-derived aggregate requires minimum processing and reduces the need for mining (like other lightweight fills) in facilities that generate greenhouse gases,” said William Heung, CalRecycle Senior Waste Management Engineer for the Materials Management and Local Assistance Division.

    Tires saved millions on California transportation

    Local governments used this tire material to expand rail systems for both the Bay Area Rapid Transportation (BART) and the Metropolitan Transportation Agency in Southern California. The cushioning rubber from tires absorbs vibrations underneath the tracks.

    Along with keeping about 500,000 tires from going into landfills, these two projects saved BART and MTA millions of dollars.

    tire project aerial shot

    Tire material stabilizes a retaining wall on a hill that prevents mudslides in Santa Barbara. 

    A recent innovative road project in Santa Barbara used tire material to stabilize a retaining wall located on a hill. Because the tire material won’t degrade even when wet, engineers expect it to support the retaining wall more effectively and help prevent mudslides that can happen when water washes away soil on a hill. (View video.)

    Keeping tires from trashing California

    California’s population will continue to grow, so our efforts to expand tire recycling must keep pace.

    Over the last few years, through its grants and loans, CalRecycle has funded rubberized road concrete and other tire material projects to prevent millions of waste tires from ending up illegally dumped or in landfills.

    CalRecycle explores potential tire products as we work to reach the state's zero waste goals while preventing tire fires that pollute our air with poisonous smoke. 

    Posted on In the Loop by Syd Fong on Feb 18, 2020

  • CalRecycle Awards $439,636 to Yuba County for Tire-Derived Aggregate Road Repair Project

     

    Back-hoe filling erosion with tire-derived aggregate.

    Yuba County is home to the latest construction project to use recycled waste tires to patch up damaged roadways. Last month, 430,000 tires were utilized as filling material to repair multiple roads destroyed by recent landslides.  

    CalRecycle awarded the county $439,636 as part of the Tire-Derived Aggregate Grant Program, which funded both the purchase of the recycled tire material and the repair work.  

    Tire-Derived Aggregate (TDA) is made from shredded scrap tires and is used in a wide range of construction projects. These uses include retaining wall backfill, lightweight embankment fill, landslide stabilization, vibration mitigation, and various landfill applications.

    The material is lightweight and cost-effective, and it drains well in wet conditions. 

    As an added bonus, recycling tires diverts them from landfills and illegal dumpsites. Currently, California generates more than 40 million waste tires per year. 

    Take a look at this video to see the recent Yuba County TDA project in action.  

    Watch the youtube video for more.

     


    Posted on In the Loop by Syd Fong on Oct 7, 2019

  • Santa Barbara County Uses CalRecycle Grant Funds to Rebuild Roadway with Recycled Tires

     

    Santa Barbara County builds retaining wall with recycled tires

    How do you repurpose 81,000 recycled tires? Well, use them to create a new retaining wall, of course. 

    That’s what happened with a recent road stabilization project in Santa Barbara County.  This unique application utilized 810 tons of tire-derived aggregate to backfill a retaining wall composed of large, rock-filled, welded wire baskets called gabions. 

    In March 2018, CalRecycle awarded the county $158,241 in Tire-Derived Aggregate Grant Program funds to purchase the TDA material. 

    Prior to the project, failed soil in the embankment caused erosion to the old roadway and shoulder. The ongoing failure also created large cracks in the asphalt surface.

    But the new retaining wall is expected to have longer staying power due to the TDA material. UC San Diego researched the road repair technique and determined that TDA is seismically safe for retaining walls and for road repairs and will not degrade due to poor underlying soils or saturated conditions.

    For more information about this project, read our press release and watch our video, which includes some outstanding drone shots recorded by Santa Barbara County Public Works.  


    Santa Barbara TDA Roadway Repair Project YouTube

    Posted on In the Loop by Syd Fong on Aug 8, 2019