In the news: Big rainstorms yesterday (July 26) in Utah, southern Nevada, Death Valley, southern California.
The deserts, being made of glass-like sand, don’t absorb much water. So it all runs off, producing flash floods.
So where does all that water end up? Does it flow into the Colorado River? or Lake Mead? Does much if any end up in other lakes or reservoirs? Or does it just all run out to the ocean? This article doesn’t mention, and I don’t recall seeing it mentioned elsewhere either.
(No, Discobot, this topic isn’t similar to “How did TMZ become the go-to source for breaking ‘news’”.)
Rain in Death Valley typically winds up in Badwater Basin which then becomes Badwater Lake until the water evaporates again.
Rain falling upriver from somewhere like Lake Mead winds up in Lake Mead - that’s sort of the point of reservoir-and-dam system. If it winds up in the Colorado it doesn’t reach the sea anymore because humans use up the entire river.
Other rivers reach the sea, so yeah, a lot of the water eventually winds up there. In desert areas some flash floods wind up at temporary lakes, as in Death Valley.
SCal has created an extensive network to corral and direct storm water. Ideally, water will cooperate and dwell in retention basins and recharge the ground water. Excess is directed to often massive concrete-lined channels which eventually drain to the ocean.
With the explosion of homes being constructed, plus all the accompanying shopping centers, schools, and whatnot, the original dirt is now covered with pavement and houses. That means more water with no place to go.
Water is a precious commodity, yet most of what falls from the sky as rain must be channeled away to the ocean. The stuff that flows from hoses and faucets mostly originates from the snow pack in Northern Cal.
It sure seems everything needs to be re-engineered to better use this resource.
So, some (but not really very much) of all that rainwater is captured and put to good use, but most of it just ends up in toxic lakes where it evaporates, or runs into the sea. Yeah, what a waste in these mega-drought end-times.
Thus accumulating ever-more-concentrated salt and toxic agricultural runoff. See this recent article about the Salton Sea (soon to be renamed the Toxicon Sea):
Lake Mead is there to power Hoover Dam. Other uses are secondary.
Las Vegas does get about 90% of its drinking water from Lake Mead, but I assume that like drinking water everywhere, there is a whole megasystem that is dedicated to purifying the source water.
Where I live, and surrounding nearby places, there are water vending machines all over the place. They sell water for 35 cents a gallon, and you have to bring your own bottles. The water is just municipal water, allegedly run through a half-dozen treatment processes right there in the vending machine. These machines must be doing something to the water, as the result is palatable, as compared to direct tap water at home.
Wiki (Watersheds of North America - Wikipedia) has a good map of which ocean the rainfall on the USA ends up. Note that there are 6 basins where it never reaches an ocean. (The little closed areas on the map.) One of them is the Badwater basin, around Death Valley, mentioned above
Also, this what happens naturally. But we humans have made various constructions to divert the natural waterflow. Sometimes to generate electricity, to irrigate crops, or often just to channel it to avoid flooding. But we’re learning that much of that can contribute to emptying of underground aquifers, and losing to the oceans fresh water that is a valuable resource.
What am I missing? That wiki page lists 6 “endorheic” regions (that don’t drain to any ocean, sea, gulf or Great Lake) but I can only see 4 closed areas on the map, 3 of them “little” and one big one covering most of Nevada and surrounding area. (ETA: Plus a link to another wiki page that list several dozen more really little such areas.)
I believe this map shows the Great Basin (covers most of Nevada) and the Badwater Death Valley Basin as one big brown area – the Badwater part is in the south, going into California. Also, the last 2 basins listed merge together down in central Mexico, and they too are shown as one area on the map.
Why they are called separate basins when they merge together on the map is a question for a geologist. Guessing, the rainfall in the areas flows to different end locations, so they are separate, but neither ever reaches an ocean
Badwater is called that due to a local spring that is full of brine and has been since before the Europeans showed up. It’s called “badwater” because the water is naturally so full of salt it’s undrinkable for humans. The basin has been a salt flat for many thousands of years. That isn’t the fault of human activity.
The Salton Sea is a different story. That basin has a long history of filling up with water then drying out again, but it’s both human ag run off that made it toxic and human use of the Colorado river that’s drying it out again right now.
New York City’s water undergoes minimal treatment, as noted here. There’s UV disinfection as of 2013, but 90% of it is unfiltered. The one filtration plant was built in 2006. Which is amazingly little treatment for a city water supply. Prior to the 21st Century it was largely untreated.
Note that the Great Basin is actually made up of a number of smaller endorheic basins. For example, in the north is Harney Basin in Oregon. The area around Lake Tahoe is another. And since Death Valley is considered part of the Great Basin, the Badwater Basin is another.
Although it’s more animal shit than people shit. NYC water also contains tiny copepods, a relative of shrimp, which actually contribute to water quality. They are also very much NOT kosher animals, which caused a bit of a freak-out among the Ultra-Orthodox Jews in the city some years back.
Yeah, all those “natural” springs and mountain streams that people tout rapturously have animals living in them and runoffs from the banks. But the volume of water moving through dilutes the add-ons to minute percentages. It’s only when the volume of pollution overwhelms the volume of water that it becomes problematic.
Rochester gets most of its water from two Finger Lakes that the city owns and bans any development around. That means it also has some of the best tasting water in the country. Even so, we don’t drink it straight.
WHERE DOES MY DRINKING WATER COME FROM AND HOW IS IT TREATED?
Since 1876, Rochester residents have relied upon Hemlock Lake, with Canadice Lake added in 1919, for their drinking water supply. The City also purchases water from MCWA’s Shoremont treatment plant on Lake Ontario. (MCWA water quality information is available at www.MCWA.com.) The Hemlock Water Filtration Plant is a direct filtration plant with a capacity of 48 million gallons per day and employs processes involving pH adjustment, coagulation, filtration, disinfection and flouridation.
Filtration & Disinfection:
During coagulation, chemicals are added to untreated water, causing the natural particulates to clump together into larger particles called floc. The floc is removed by filtration and the water is then disinfected with chlorine.
Corrosion Control:
The City uses carbon dioxide to adjust water pH as part of its corrosion control strategy. A pH range of 7.7-8.0 is maintained to ensure water in the distribution system is stable and not corrosive to pipes. This pH range, along with the natural hardness and alkalinity levels in the water have ensured that the City is in compliance with the Lead and Copper Rule.
Fluoridation:
The City of Rochester is one of the many New York water utilities providing drinking water with a controlled low level of fluoride for consumer dental health protection.
Yes, we get Hemlock Lake water. We’ve not only heard the jokes for 150 years, we make them.
Small municipalities may obtain water from private wells. We lived in one of these, and each property owned a “share” in the water company. Our water was untreated, unless a pipe busted somewhere in the system, and then it would all be flushed out with chlorine for “x” number of days. The water was incredibly hard and had a high iron content.
Our current property in AZ has a well. We paid quite a hunk of change for it. We tested the water, and all levels of stuff they test for were very low.
Except iron.
We have a RO filtration system to eliminate as much iron as possible.
And there was NO coliform detected.
Because of my kidney problem children, I drink bottled water.
