PROJ00066

• Contract/PO #: C153601
• Contractor Name: Louisville, City of
• Contract Type: Loan
• Water District: 6
• County: Boulder
• Bill Number: FSL
• Loan Projects - Doc Type: Contract Documents

a monthly basis wherein the annual demand will be converted to a monthly hYlSt?graph and run
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against historic yields from the above water rights. .'. . '''''<ii;;}

This model will be capable of simulating on a monthly basis anticiplllell yi il City water rights
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during the various hydrologic cycles represented in the historic recoiil~_ water rights flows
into storage vessels, accounting for evaporation and seepag~!~~g}dentifyiJ" yields of projects in
order to indicate the City's ability to withstand historic drou!lt\#f~g magnitude and duration
with its water rights portfolio. .' ..j1~) ''v

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Input will be based upon historic stream flows and dilCI!.\i;t\f;.~iiOns (using the SEO electronic
diversion records) linked with the City's monthly demand"rOgraPhS in a spreadsheet format. Input
will also include: the capacities of the City's physical conveyance system, the City's current and
anticipated ownership of water rights and the capacity of other conveyance facilities routinely used by
the City in the conveyance of its raw water. All values will be in acre feet, or a flow rate in cubic
feet per second. Output will be in spreadsheet form identifying demands met from direct flow rights
or storage releases. Water surpluses will go to storage where space is available or be spilled.
Monthly and annual totals will reflect average, minimum and maximum usage, yields, surpluses,
spills, and rerum flow credits (where applicable).

Flexibility will be built into the model to allow specific years of the historic period to be simulated;
expansion of current water rights ownership, conveyance improvements, or the addition of storage
facilities; the acquisition of additional water rights; or inclusion of a project which adds raw water
supply to the City's system. The additional raw water supply may be specified by the user as
individual monthly values for the entire simulation period or as annual values which may be used in
aily fashion during a given year on an as-needed basis (e.g., annual C-BT quotas).

4.0 EVALUATE EXISTING RAW WATER SUPPLY SYSTEM

Using the computer model developed in Task 3.0, the Consultant will evaluate the reliability of the
City's existing system under the three water demand scenarios. This assessment will indicate the
ability of the City's currently owned water rights to meet existing and two future demand scenarios
under a variety of runoff conditions and the drought condition: 'It will also show the "level of

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