_PERMIT FILE - M1981302 ‎(24)‎

• Permit No: M1981302
• IBM Index Class Name: Permit File
• Doc Name: WATER RESOURCES
• Media Type: D
• Archive: No

I
South Boulder Creek and has an average yield of 5.47 acre-feet
per share and a critical year (1954) yield of 2 . 67 acre-feet
per share. Water is generally available in the ditch from
May through August. Water diverted from the ditch has
historically been supplemented by ground water flowing from
the higher areas on the west and by return flow from upland
irrigation.
Ground water. Ground water occurs on the site at depths of
less than 1 foot to more than 5 feet. The Pierre shale
underlying the alluvial sand and gravel forms an impervious
barrier to downward ground water flow. Water moving into the
ground water system percolates vertically until contacting
• the existing water table or the shale surface. Ground water
then moves laterally downgradient towards the location of
surface discharge.
Ground water in the sands and gravels is in direct hydraulic
connection with the surface water flowing in South Boulder
Creek and the irrigation water flowing in the Dry Creek No. 2
Ditch. At times during the year water moves freely from the
creek to the ground water system. At other times, the direction
of flow is reversed with ground water sustaining a base flow
• in the creek. In the late spring and early summer, the water
table may. rise up to 5 feet, depending on location, as a
• result of recharge from precipitation, stream-flow and irrigation.
C-2