In the last post I implicitly accused you all of using too much water: you seemed to take it well. Now that you're grumpy with me, I'm ready to take it all back. Yes, we Americans consume more water (the USGS calls it "withdrawal") than most other countries, developed or developing (yes, China takes the biscuit, but they've got lots, for now). Yes, we squander lots of fresh water in our homes by flushing toilets, bathing, and washing our clothes. All true. But if the American people all stopped using water in their homes entirely tomorrow, water would still be an endangered resource for us.
Who's getting it all? Industry and agriculture, I'm afraid. Nor are those industries actively pursuing less water-intensive technologies, except where it suits them financially. About one sixth of all U.S. water usage is residential supply for personal use. One third of our "withdrawals" of fresh water goes toward agricultural irrigation. Good cause, actually, and it gets put on the crop and soaks into the ground, but it's still lost water in many ways. Evaporation claims much of the water used for irrigation, and you can't control where it comes back down. Certainly not Phoenix, where the water comes from far away in pipelines from reservoirs and evaporates to the air never to be seen again. At least not in Phoenix.
Fully half of America's total water usage is for industrial cooling, much of it consumed by evaporating devices called "cooling towers." Wherever heat needs to be removed from a process or material, evaporation, the most efficient means of heat transfer on the planet, is called into service. One pound of water, in evaporating, removes 970 BTU of heat from its surroundings. Nothing else compares, not even a cold Bud. And again, the evaporated water is lost to the immediate environment, since rain isn't fair. Most industrial processes require the services of cooling towers, but the single most demanding industry is electric power generation, including nuclear power. Some plants use salt water, but not all.
Don't give up. We all need to become more aware of our consumption of fragile resources, and your water-saving strategies at home are important culturally and politically, as well as financially in your water bill. But, as in so many issues, the picture is much larger than our individual water habits, and we will have to participate in a much larger discussion to bring sanity to our national energy and resource policies. Meanwhile, be glad when your water bill shows that you've been conserving. It's up to us regular folks to lead the charge, and in the greatest democracy in world history, government and industry must surely follow, hopefully in time to protect our fresh water supply from depletion.
Who's getting it all? Industry and agriculture, I'm afraid. Nor are those industries actively pursuing less water-intensive technologies, except where it suits them financially. About one sixth of all U.S. water usage is residential supply for personal use. One third of our "withdrawals" of fresh water goes toward agricultural irrigation. Good cause, actually, and it gets put on the crop and soaks into the ground, but it's still lost water in many ways. Evaporation claims much of the water used for irrigation, and you can't control where it comes back down. Certainly not Phoenix, where the water comes from far away in pipelines from reservoirs and evaporates to the air never to be seen again. At least not in Phoenix.
Fully half of America's total water usage is for industrial cooling, much of it consumed by evaporating devices called "cooling towers." Wherever heat needs to be removed from a process or material, evaporation, the most efficient means of heat transfer on the planet, is called into service. One pound of water, in evaporating, removes 970 BTU of heat from its surroundings. Nothing else compares, not even a cold Bud. And again, the evaporated water is lost to the immediate environment, since rain isn't fair. Most industrial processes require the services of cooling towers, but the single most demanding industry is electric power generation, including nuclear power. Some plants use salt water, but not all.
Don't give up. We all need to become more aware of our consumption of fragile resources, and your water-saving strategies at home are important culturally and politically, as well as financially in your water bill. But, as in so many issues, the picture is much larger than our individual water habits, and we will have to participate in a much larger discussion to bring sanity to our national energy and resource policies. Meanwhile, be glad when your water bill shows that you've been conserving. It's up to us regular folks to lead the charge, and in the greatest democracy in world history, government and industry must surely follow, hopefully in time to protect our fresh water supply from depletion.
Posts
No comments:
Post a Comment