Click for next page ( 19


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 18
8 Fifty-five percent of all litter is deliberate, consisting Rank Objective Factors Subjective Factors mostly of convenience packaging and products. The 40 North Carolina New Mexico remaining litter is accidental, resulting from uncovered 41 trucks, unsecured loads, loss of vehicle parts, trash can Tennessee North Carolina spills, and human carelessness. 42 Kentucky Kentucky The sources of roadside litter vary greatly depending on 43 Alabama Tennessee type of roadway. For example, 50% of the litter on urban freeways and 53% of litter on rural freeways appear to be 44 South Carolina Nevada accidental, whereas accidental litter on rural local roads 45 Louisiana West Virginia and rural state highways is 36% and 39%, respectively. Past surveys have revealed that 97% of litter comes 46 New Mexico South Carolina from four sources: pedestrians (42%), vehicle occu- 47 Arkansas Arkansas pants (20%), uncovered or unsecured loads on trucks 48 West Virginia Alabama (21%), and open vehicle beds where items had been improperly stowed (14%). 49 Nevada Louisiana 50 Mississippi Mississippi The Institute for Applied Research (IAR), in an analysis Source: Spacek (2008). of 62 litter surveys using similar methodologies, has deter- mined that the average rate of litter has been decreasing at Litter abatement campaigns in America have been studied about 2% per year (IAR 2006). The analysis accounted for (Rai University 2008) and found to be unsuccessful because major factors that significantly affected litter rates (i.e., traf- of the following reasons: fic volumes, median income, number of vehicle occupants, rain-temperature index, population, distance from the city, Littering is not important or of much interest to most and the duration of any litter programs in service). In this people. same research, the IAR evaluated the cost-effectiveness of People generally had little previous involvement with five major methods or strategies for controlling litter. The the issue. cost-effectiveness of the five strategies is shown in Figure 1. Antilittering behavior produces only slight personal benefits and does not lead to a personal efficacy because The two most expensive ways to remove or prevent litter litter cleanup depends on the collective action of many from streets and roadsides are paid litter pickup programs, people. which cost $1.29 to remove one item of litter, and beverage Proper litter conduct may result in personal costs and container deposits, which only reduce beverage container inconvenience. litter at a cost of $4.24 per item. Paid litter pickup programs The personal benefit-to-cost ratio is low. immediately reduce litter by 90%, but litter builds back The demand for a litter-free environment is not strong up again to near precleaning levels within 7 to 31 weeks. or universal. Deposit programs immediately reduce fresh container litter, The litter abatement message is difficult to develop as but they have no effect on the major components of litter, it must be tailored to each target group. such as takeout food packaging. VISIBLE LITTER STUDIES Visible litter composition studies are the most prevalent type of research that is documented. DOTs and their state col- leagues have been performing visible litter studies since at least the 1990s. Florida, Georgia, New Jersey, Texas, and several large municipal centers have conducted litter com- position studies. The reasons for conducting these studies include determining the composition of litter, identifying the likely sources of litter (i.e., deliberate or accidental), identi- fying the locations and facilities where litter accumulates, as well as establishing baseline conditions against which to measure changes in litter rates over time. Stein and Syrek (2005) have synthesized the results from numerous visible litter surveys conducted in the United States and report the FIGURE 1 Cost-effectiveness of popular litter abatement following: strategies (Source : IAR 2002). Note: AAH = Adopt-A-Highway.