how much water evaporates from the CAP, the SRP canals, and from tempe town toilet, which the tempe rulers call tempe town lake?
With so much water in air, why no rain?
Feb. 26, 2006 12:00 AM
Ok, you can stop sending me mnemonics for remembering the difference between a stalactite and a stalagmite. The first two or three were very helpful. The next 30 or 40 got a bit repetitive. But thank you very much for sharing.
Next, since I am always looking out for your best interests, here's a tip: Go out to the Pueblo Grande Museum and Cultural Park, 4619 E. Washington St. in Phoenix, and check out the exhibit of aerial photos of Phoenix and the Valley from the 1930s. It's pretty cool. Actually, Pueblo Grande is pretty cool, anyway, but the photos are an added benefit.
Now, let us take up today's question, which comes from a guy whose visiting sister-in-law wants to know:
Has anybody ever calculated how much water is lost from the Valley's canal system through evaporation?
OK, let's start with the Central Arizona Project. The 336-mile canal has a top capacity of about 2.2 million acre-feet, and CAP estimates it loses 3 or 4 percent of its water to evaporation. An acre-foot, as I'm sure you know, is enough water to cover 1 acre 1 foot deep. It's about 325,851 gallons.
So why not cover the canal and save all that water? Because that would have quadrupled the $4 billion cost of building the thing.
Next, Tempe Town Lake. It loses about 1,900 acre-feet per year or about 1.7 million gallons per day, according to Tempe.
According to the Salt River Project, it loses about 125,000 acre-feet a year to evaporation and seepage from its system of six lakes on the Salt and Verde rivers and 1,230 miles of canals and ditches.
If you go to www.srpwater.com/dwr you can get the daily numbers on reservoir levels, including the rate of evaporation.
What is the origin of the name Kyrene?
Kyrene was a station on the Arizona & Eastern Railroad about six miles south of Tempe, according to Arizona Place Names by Will Barnes. A lot of hay and cattle got shipped out of there in its heyday between 1888 and 1896.
It is thought that that classically educated rascal Darrell Duppa, who also came up with the names Phoenix and Tempe, named it for Cyrene, which was a city in what is now Libya and the home of Simon, the guy the Scriptures tell us was dragooned into helping Jesus carry his cross.
Or it might have come from Kyrenia, a seaport on Cyprus.
Reach Thompson at firstname.lastname@example.org or (602) 444-8612.