WSP04784

• File Number: 8103
• Description: Arkansas river Basin Legislation
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 9/1/1968
• Author: W W Wheeler and Asso
• Title: Water Legislation Investigations for the Arkansas River Basin in Colorado Volume II Comprehensive Report September 1968
• Water Supply Pro - Doc Type: Report/Study

O~2001

The results of these studies are presented in Table 7. The dif-

ferences between the various periods for the total of all ditch diversions

and the Fort Lyon Canal and Amity Canal shows that there is reasonable

agreement between results for the overall period and the 1951-1966

period. This indicates that the monthly results shown in Table No.8,

and which are discussed next, are fairly representative of present con-

ditions. However, it should be noted that the 1942-1950 period of runoff

and diversions are generally much higher than the long term of 1951-

1966 values.

Additional computer studies were run on a monthly basis for the

long term period of the experienced river flows and ditch diversions.

The procedure followed to find the monthly variations was identical

to that for the annual studies. The same river stations and ditches

were used for the monthly study as were used in the annual study. When

the winter diversions were variable and contributed to the scatter of

the annual diversions and the summer diversions were stable, the supply

Is better than indicated in the annual study. Conversely, if the diver-

sions during the winter period were stable and contributed to a more

stable total when the summer months varied greatly, the annual total

would indicate that the ditch had a better balanced supply than

actually occurred. Table No.8 shows the results of these studies.

In ~nalyzing the results given in Table No.8, the arithmetic totals

of the monthly values are similar to those obtained by taking the

worst month of record and adding the values to get the worst year of

record. In other words, the worst year of record does not necessarily

contain all of the worst months of record and the 50 percent year does

not contain all of the 50 percent months.

The table shows that the monthly distribution of the canal diver-

sions and river flows vary greatly and that the inflow to the basin is

much more stable than the outflow. The flow expected at Canon City

for 50 and 90 percent of the time in August varies from 47,800 to 28,600

acre-feet. Diversions by a canal having a good water right, for

example the Rocky Ford Di tCh, were 5,700 and 4.400 acre-feet for the

50 and 90 percent diversions in August. This variation is dependent,

in part, upun precipitation and other cl imatic factors. A ditch with

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