You notice something when there is less of it.
Back in February when I was hiking in Big Bend I knew exactly how much water I was consuming. When you’re in a desert, you have water on your mind. And lots of time to think random thoughts. I’m finally getting to blog this a couple of months later.
I finish one litre before setting out in the morning. I use a small portion of that to mix in with my powder milk and granola for breakfast and drink the rest down while packing up and getting ready. I drink my next litre while hiking about 10 miles and with lunch. It was still pretty cool during the day back in early February so I didn’t need to replenish a lot of water. By late afternoon we arrive where we were going to camp for the night. I use about two litres between then and going to bed. I drink about a litre and use the rest to cook dinner. A tiny bit goes to cleaning dishes, brushing teeth, and sponging off.
So four litres per day kept me comfortably alive and hydrated, not counting the water in the whiskey. I’m calling this one unit of minimum daily water (MDW). Water is heavy. My backpack with four days of food usually weighs in at around 11 kg (24 lbs). Four litres of water is an additional 4kg (9 lbs). A day’s worth of water is 25% of the weight I have to carry.
Though we were pumping and filtering water from a creek during our recent trip to the Ouachita National Forest, I kept track of our water usage. Mine was about four litres a day again, or one MDW. Vivian’s was slightly less. Evan hardly drank any. We never carried more than a litre because there was a creek always nearby.
At home, we domestically consume about 100 gallons a day per person, the most in the world. That is 379 litres. Some drier western states ironically have higher usage, with Nevada and Utah coming in closer to double the average. But it’s not because we drink 100 times more water at home than I did while hiking. We typically consume most of it for showering, flushing, and washing. A gallon of water at HEB costs about a buck. But a gallon of clean water out of the municipal water mains costs less than a cent. So there is very little financial incentive to cut back on our water consumption. During winter storm Uri, millions didn’t have access to running water. And many more (including us) were under a boil-water notice for days. When you’ve got to get your water in gallon jugs from HEB you’re suddenly like me in Big Bend – you’re down to your 4 litres per day plus what you need to flush the shitter a couple of times. People in Ethiopia and Mozambique use the least water in the world – about 15 litres (less than 5 gallons) per day on average, about 20 times less than us. And it’s not because Ethiopians and Mozambicans are uber water conscious. They unfortunately don’t have ready access to cheap and plentiful clean municipal water.
The water puzzle gets weirder when you think about total water usage. I did mention that walking in the desert gives you plenty of time to ponder.
Besides drinking water and using it to wash, almost everything we eat or use requires water to grow or make. The coffee required to brew a single cup requires 130 litres to grow. A pizza margarita requires 1,600 litres, mostly to grow the wheat. Beef is the most water intensive food, coming in at a whopping 16,000 litres per kilogram. It is inefficient because we must first grow something using water and photosynthesis, and then feed that to the cow and then we eat the cow. Cows are more inefficient at turning water into meat than goats or sheep or chickens. But it could be worse. Imagine if we favored lion steaks. Then we’d have to feed cows to a lion before eating the lion.
Globally, we use about 75% of the fresh water that we extract from lakes, rivers, and springs to grow things we eat. Energy production requires a lot of water too. When we burn fuels to make electricity, huge amounts of water are used to heat and cool things. But if we are careful and don’t pollute the water it can go back into circulation. Not so when we drill for oil and gas both of which use vast quantities of water that is too polluted and will require thousands of years of filtering by nature to make usable again. Fracking (fracturing) literally uses the force of water laced with chemicals to break shale rock deep underground to release the gases stored in the rock. A typical fracking job requires 15 million litres of water or six olympic sized swimming pools full of water. The resulting polluted water either remains underground or is typically disposed off by drilling a dry well and pumping the water into it. That is 3,785,000 MDWs (enough to live in Big Bend for almost four million days or 10,000 years!). Solar and wind farms require enormous amounts of water to build solar cells and steel and fiberglass turbines. But after that they don’t need water to operate.
An empty plastic water bottle requires seven litres of water to make. A sheet of paper needs 10 litres. Making a car costs about 400,000 litres of water.
Scientists and economists call the total water usage our water footprint. It is the total amount of water needed for the production of goods and services and to live. Figuring out a country’s water footprint means adding all the water used plus the water inherent in products imported, then subtracting the water in exports. Americans have the biggest per capita water footprint. Interesting things happen when you consider where goods are made or grown and where they end up. When Uncle T exports soybeans to China, he is also exporting American water. Being the largest exporter of cereal grains means that America exports huge quantities of consumed water. Like other natural resources, fresh water isn’t distributed evenly over the world. So there isn’t anything inherently bad about exporting water if the exporter is rich in water. California and Israel grow and export a lot of vegetables and fruits. And they don’t have a lot of water. Someday we may decide what to grow or make and what to export or import by considering our water footprint.
Uri is just a memory. I’m back home from Big Bend. I won’t think about this till the next time I’m not around a faucet dispensing clean, almost free water. May be I’ll eat a ribeye and buy a new car and take a long shower while pondering about what kind of a planet we will leave for our kids. It doesn’t take a hydrogeologist or a walk in the desert to guess that water or the lack of it will play an important role in the future.