The effects of deposit systems on litter reduction are well documented through pre and post bottle bill surveys. The percent of litter reduction in states where studies were conducted, fall within a range that varies by only 14 percentage points. When outliers were removed, beverage container litter reductions have consistently been between 70 and 84%, and total litter has been reduced between 34 and 47%.
| State | Beverage Container Litter Reduction | Total Litter Reduction |
|---|---|---|
| Hawaii | 38–53 [14] | n.a. |
| Iowa | 76%[11] | 39% [12] |
| Maine | 69–77%[7] | 34–64% [8] |
| Michigan | 84%[9] | 41%[10] |
| Massachusetts | n.a. | 30–35%[13] |
| New York | 70–80%[1] | 30%[2] |
| Oregon | 83%[3] | 47%[4] |
| Vermont | 76%[5] | 35%[6] |
Sources
[1] Final Report of the Temporary State Commission on Returnable Beverage Containers. March 27, 1985. p. 62.
[2] Projection from Center for Management Analysis, School of Business and Public Administration of Long Island University. New York State Returnable Container Act: A Preliminary Study (1984).
[3] Oregon Department of Environmental Quality, Oregon's Bottle Bill: The 1982 Report. p. 26.
[4] Ibid.
[5] U.S. General Accounting Office. Report to the Congress by the Comptroller General of the United States, Potential Effects Of A National Mandatory Deposit On Beverage Containers. December 7, 1977. p. 54.
[6] Ibid.
[7] U.S. General Accounting Office. Report by the Comptroller General of the United States, State's Experience With Beverage Container Deposit Laws Shows Positive Benefits. December 11, 1980. p. 9.
[8] Ibid.
[9] Michigan Department of Transportation, Maintenance Division. Michigan Roadside Litter Composition Survey, Final Report. December 1979.
[10] Ibid.
[11] Iowa Department of Transportation, Highway Division. Litter Survey. April 1980.
[12] Ibid.
[13] Environmental Action Foundation. Bottle Bills in the 1980's: A Handbook for Effective Citizen Action. August 1987.
[14] Extrapolated from International Coastal Cleanup Data 2004–2007, as found in "Report to the Twenty-Fifth Legislature, State of Hawaii." Hawaii Department of Health. November 2008. Table 4.