How Much Trash will We Generate in 2030? One recent study predicted America will generate 300 million tons of trash by then. The study used U.S. Census Bureau data to estimate population growth. It also assumed that we would have the same kind of garbage in 2030 as we do now. Census data is fine, but garbage growth is as dynamic as population growth. Garbage evolves and changes. This dynamic quality is why most predictions of the amount of trash in the future are too high.

As I thought about these 300 million tons, I wondered: If we go back 24 years to 1982, and predict forward to 2006 (the report started with 2006 data), how close would we come to the U.S. Environmental Protection Agency's (EPA) current estimate that we produced 250 million tons of trash in 2006?

Estimates of the future size of the waste stream rely on a number of variables. The easiest is population growth. The safest prediction is that more people means more garbage. After all, more people need more things, eat more food and have more houses. Census Bureau data makes figuring out population increases relatively easy.

The state of the economy is important because we make more garbage in good times than in bad. When the economy is sputtering, we can't afford to buy as many things as we used to. Manufacturing and construction decline. Garbage generation goes down. We are seeing this happen today in our current recession. I've seen numerous news articles about garbage generation lagging in many parts of the country as a result of the slow economy. Fortunately, long-term projections can be made based on historical economic trend data. Unfortunately, these always are optimistic because who wants to predict a recession?

Predicting trends in material use is trickier. Think back to 1982 (if you are old enough). Everyone read newspapers. The Internet existed for a small group of people and the World Wide Web was an idea rolling around in the back of Tim Berners-Lee's mind. E-waste was old television sets. We still used computer tab cards. Mulching lawnmowers had little market share. The waste stream was heavier because it had four times more glass and metal than plastic. polyethylene terephthalate (PET) soft drink bottles were beginning to displace glass bottles but the PET peanut butter jar didn't exist. In all, 300 million tons of trash would have been a reasonable estimate for 2006.

Predicting changes in how we manage our trash is hardest of all. Waste-to-energy was all the rage in the early '80s. EPA's Subtitle D landfill regs wouldn't be issued until 1991. The garbage barge didn't sail until 1987. Anyone who predicted the rise of recycling, grasscycling or backyard composting would have been dismissed as a dreamer.

Guessing the size of tomorrow's waste stream can be fun, just like all attempts to predict the future. However, we need to be very careful when we base public policy on these guesstimates. We need to be especially careful when they are used as the basis for spending public money to build waste recycling, compost or disposal facilities. We made this mistake in the '80s and ended up with oversized disposal facilities that were built for yesterday's garbage. The tax payer was the loser. Let's not make that mistake again.

Opinions in this column do not necessarily reflect the National Solid Wastes Management Association or the Environmental Industry Associations. E-mail the author at: cmiller@envasns.org.

The columnist is state programs director for the Environmental Industry Associations, Washington, D.C.