7777

• UCREFRP Catalog Number: 7777
• Author: Ward, R. C.
• Title: Proceedings 1993 Colorado Water Convention, Front Range Water Alternatives and Transfer of Water from One Area of the State to Another, January 4-5, 1993, Denver, Colorado.
• USFW Year: 1993.
• USFW - Doc Type: \
• Copyright Material: NO

Q: What legal framework exists that would support interruptible
supplies and the resulting change in use with interrupted return flows
other than injurious impacts?

A: If you were to interrupt the diversion by a ditch company and
allow that water to be taken by a city elsewhere for one year or two
years out of 20, it is no different in some respects than simply
drying up that land. There would be an interruption in the return
flow regime associated with that agricultural land. And it would have
to be dealt with in a water rights change case. I suspect the
problematical difficulty of that interruption of return flow would be
less severe and more easily accommodated if you were doing it on an
interruptible basis that was less frequent. The City of Boulder, one
of our clients, has been exploring the interruptible supply concept
with a couple of ditch companies in the Boulder Creek basin. That is
one issue that has come up. It does not appear to be an
insurmountable one. Legally, it would have to be addressed in the
same context as the water rights change that would allow you to take
that water permanently off the land.

Q: To what degree does your study define policies of others such as
adjacent states, federal -- both Bureau of Reclamation and Bureau of
Land Management -- or compact entitlements?

A: We did not look at other states or the federal government with
respect to policies except in our assessment of where water supply
planning has been and where it is going in Colorado, in which we
acknowledged there seem to be certain directions where the federal is
going in its permitting. Those directions are strongly aimed at
minimizing environmental impact, forcing or trying to encourage states
to use other available alternatives that have less environmental
impact. But we did not categorize them in our study. That would be a
very valuable addition to any sort of assessment like this.

Q: Use of nontributary Denver Basin aquifers as a dry-year source:
is this at odds with existing Senate Bill 5 legislation that has
already allowed for mining of this source which is not specific to
dry-year supply water? How would you suggest changing this
legislation since the barn door has already been left open to the
appropriation of this source.

A: Senate Bill 5 has allowed for appropriation of nontributary
groundwater. It does not necessarily address nor does it preclude the
use of that water as a dry-year supply except that it does have an
annual limitation for diversion equal to an estimated total capacity
in that aquifer. The way nontributary water might work as a dry-year
supply would be that you wouldn't pump more than a nominal, standby
amount, just enough to keep the well machinery working in 19 out of 20
years, but maybe one out of 20 years you would have to pump it quite
intenSively. There may need to be some modifications to the
legislation to allow for that flexibility. I think the result would
be you would have much less average depletion of groundwater if you
did it under a dry-year standby basis than if you used it under an
exclusive supply basis.

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