PANNA: Caltrans’ Excessive Herbicide Use on California Roads


Pesticide Action Network Updates Service (PANUPS)

Caltrans’ Excessive Herbicide Use on California Roads

April 19, 1999

A recent report by Californians for Alternatives to Toxics (CATs) reveals that California Department of Transportation (Caltrans), in conjunction with county road agencies, douses California roadsides with more than 132,000 gallons of liquid and 93,000 lbs. of solid herbicides each year. Caltrans applies approximately five gallons and two pounds of chemical weed killers per mile on the state’s 15,000 miles of highways. In addition, CATs found that 51 of California’s 58 counties rely on herbicides to kill weeds, and use on average, more than one pound and one gallon of chemicals per mile along the 64,000 miles of road under county management. In 1992 Caltrans pledged to reduce roadside spraying by 50% by the year 2000, however, no clear measures towards this goal have been taken.

Of the eight herbicides most commonly used, the U.S. Environmental Protection Agency has identified six as possible human carcinogens, while four are linked to birth defects. Seven of the eight chemicals are toxic to fish while four are harmful to birds. Four of the herbicides have been found in groundwater by California’s Department of Pesticide Regulation, and three quarters may be air pollutants.

“What this report shows is that Caltrans and the majority of county road agencies are putting appearance first before the health and safety of Californians. Moreover, herbicide spraying occurs often without the knowledge of neighboring communities and people who regularly work and travel on those thoroughfares,” said Patty Clary, Executive Director of CATs, an Arcata-based non-profit research organization committed to reducing pesticide use in California.

The study by CATs is the first of its kind to survey herbicide use on the freeways under Caltrans’ jurisdiction and roads under county ownership. CATs spent two years gathering data from Caltrans and road agencies in all 58 counties. Caltrans, the single largest user of herbicides in the state, spends an estimated US$6 million a year on herbicides- more than a quarter of its annual budget earmarked for “vegetation control.”

Alternatives Exist

Despite agency reluctance to reduce the use of herbicides, several affordable non-toxic alternatives exist. Among them is an Integrated Vegetation Management Plan (IVM) which includes several treatment methods. Past studies have found the use of steam spraying machines highly effective in killing weeds, and that corn gluten inhibits weeds from sprouting.

Both alternatives are currently being explored in isolated, underfunded studies by Caltrans and the University of California, as is the use of fire-resistant native plants to choke out unwanted weeds.

Based on their investigations, CATs strongly urges Caltrans and county road agencies to change their roadside management plans to ensure the health and safety of California residents and wildlife. Specific recommendations for state and local agencies include:

*Invest as much money in alternative weed management plans as is currently spent.

*Advanced on-site warnings of herbicide use should be posted during the transition from chemical to non-chemical roadside treatment.

*Audit existing records of herbicide use to assess actual annual cost of herbicide spending in order to provide an economic comparison for alternatives.

Source: Californians for Alternatives to Toxics, “The Poisoning of Public Thoroughfares: How Herbicides Blight California’s Roads,” Spring 1999. Copies available from CATs for US$12 plus $2 shipping.

Contact: Californians for Alternatives to Toxics, P.O. Box 1195, Arcata, CA 95518; phone (707) 822-8497; fax (707) 822-7136; email; web site



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