If water supply is a big problem in the States, can’t we effectively store stormwater in some way and replenish our supply?
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I mean you absolutely can for personal use, except in some states with some minor restrictions from older water rights issues. The idea being that if you collect rainwater you are taking it from someone else it would have potentially flowed to naturally. Its rather outdated logic now though, and most harvesting laws have been repealed.
The problem though is that the main reason we have water shortages is because of agriculture. Makes up something like 70% of water use. Crops (including those we feed to livestock) can need tons of irrigation, and virtue of being an open field are already collecting quite a lot of rainwater.
Like if you zoom in on a random spot in the US that isn’t a national park or desert or mountains it’s just fields back to back to back. There’s just no empty space near good farmland for supplemental rain collection. Cause if there were they would put a farm there instead.
Getting water to drain and replenish groundwater can’t be done if it’s in a bucket. Not that this sort of replenishment is happening at a good rate, civilization has done a number on the systems which replenish groundwater.
Moreover, you greatly underestimate the amount of water you’d need to store. A residence will consume around 100 gallons of water per day, per person. Storage of rainwater at that scale is simply unreasonable for most areas.
Storm water lands everywhere. Capturing it would be a nightmare
If you don’t capture it where it lands then it will bring all sorts of nasties with it. Cleaning it would be super expensive.
Storing water is expensive. Requires a massive area and constant monitoring/treatment to stop nasty stuff growing in it.
Transporting water is expensive. Requires massive infrastructure of pipes, pumps, cleaning stations etc. To be fair this problem exists regardless of storms, but it does kind of help to understand why areas prone to storms can’t necessarily share their water with other regions more desert like.
I work in water treatment, water supply & water quality.
The reason that storm water isn’t harvested is because it is very low quality water. It is concentrated with the nastiest of nasties that are incredibly difficult to remove.
Without exaggeration, it is easier to treat sewage water than storm water… there is too high of a concentration of industrial and synthetic chemicals coming off the road. At least literal shit is biological and can easily be broken down.
Edit: Bugger, didn’t realise this was ELI5, so here goes:
Cars and factories make things that we can’t drink, and can’t make drinkable. So instead we get our water from rivers and other natural things.
We can they are called wetlands, swamps and wetlands soak up water in heavy rains and then it slowly drains out.
We already do, these are called reservoirs and cisterns. Building them is not always practical, and there are still limits to their capacity, no matter how many you build.
The truth, however, is that the water supply isn’t the problem. It’s growth far beyond the capacity of nature to sustain. The Federal government knew that the draw on the Colorado river would exceed its ability to replenish back in the early 1990s. Here’s a citation from a 1993 study:
>Under conditions of long-term flow reductions and current operating rules, these reservoirs are drawn almost completely dry.
Since then, Colorado’s population has shot up by 61%, Nevada’s population has shot up by 128%, and California has grown by 26%. An impending disastrous drought wasn’t sufficient to blunt the construction of new housing developments. Decades of intransigence and procrastination by office holders has produced a reckoning which cannot be averted anymore.
The answer is either “we do”, or “surface area”.
Most of the water we use comes from lakes, rivers, or reservoirs, which are all ultimately fed by rainwater. They each contain more water than merely falls on top of them, though. Water that falls on land slowly seeps through it, following gravity and pressure (i.e. rocks) and eventually finds its way into those bodies.
Collecting water that falls in developed areas is harder because it rolls off the buildings and pavement instead of soaking into the ground, and it collects lots of fun pollutants and trash along the way. Some of those things are very difficult to remove.
However, it’s not uncommon for individuals to collect *some* rainwater for gardening or the like. There is a very big difference between someone funneling the water from their roof into a barrel, and building a system that covers enough area to supply a significant number of people.
We do “collect” water into our sewers, and there are increasing efforts to purify sewage to recycle into drinkable water (the technology isn’t terribly new, even, the International Space Station has been doing this for decades). There are multiple such projects near me in Southern California and another under construction. https://eastcountyawp.com/198/Frequently-Asked-Questions
One man’s storm water is another man’s river flow or ground water replenish. Catching the storm water doesn’t make more water. Just changes who gets it.
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