Storage, in millions of gallons daily per square mile of net land area, at the Wachusett Reservoir in Massacusetts - storage computed for each of several rates of draft (draft being a determined maintainable flow in 1,000s of gallons per square mile daily).

First extensive published use of normal qqplots. Hazen uses a=1/2 to make the p values for the plots. Hazen doesn'tplot zeros but has them contribute to the sample size. The context of use is in a study of the relation between the water storage provided in a reservoir on any stream and the quantity of water that can be continuously supplied by it. To quote the paper: ... treat all the remaining variations on the basis of probabilities, using all data from a number of streams; and to study them in comparison with the normal law of error."

WachusettReservoir

Format

A data frame with 15 rows and 6 variates:

draft100

Computed storage, in millions of gallons per square mile of land area, given a draft of 100,000 gallons per square mile daily.

draft200

Computed storage, in millions of gallons per square mile of land area, given a draft of 200,000 gallons per square mile daily.

draft400

Computed storage, in millions of gallons per square mile of land area, given a draft of 400,000 gallons per square mile daily.

draft600

Computed storage, in millions of gallons per square mile of land area, given a draft of 600,000 gallons per square mile daily.

draft800

Computed storage, in millions of gallons per square mile of land area, given a draft of 800,000 gallons per square mile daily.

draft1000

Computed storage, in millions of gallons per square mile of land area, given a draft of 1,000,000 gallons per square mile daily.

Source

"Storage to be provided in impounding reservoirs for municipal water supply (with discussion)", Allen Hazen, Transactions of the American Society of Civil Engineers, Vol. 77, (1914), pp. 1539-1669.

Details

qqtest(WachusettReservoir$draft800,dist="uniform", a=1/2,type="o") will effect Hazen's original plot for a draft of 800,000 gallons per square mile daily.

qqtest(WachusettReservoir$draft800,dist="normal", a=1/2, type="o") will effect Hazen's normal qq plot for a draft of 800,000 gallons per square mile daily.