Page 21 - Yucaipa Sustainable Groundwater Management Agency - Yucaipa SGMA

4. Review simulations of future conditions and estimated sustainable yield, re-visit undesirable
results, minimum thresholds and measureable objectives

The cost estimate assumes eighteen (18) hours of preparation, travel and participation per meeting. The
TAC meetings will be attended by the project manager and two other team members pertinent to the
meeting agenda. Dudek assumes Valley District or Yucaipa GSA member agencies will reserve the
meeting location and audiovisual equipment for the meetings.

USGS Groundwater Model

The costs for this task are based on using a calibrated numerical model that integrates surface water and
recharge with groundwater. Dudek understands that the USGS anticipates having a calibrated model by
the end of summer 2018, at which point the preliminary model input files and draft documentation on
model design and calibration will be provided to Valley District. USGS anticipates publishing a final report
of the model in the summer of 2019. Dudek anticipates obtaining the preliminary model input files and
draft documentation in the summer of 2018 to begin evaluating the basin water budget, historical safe
yield, sustainable yield, data gaps, and preparing predictive simulations of future conditions to estimate
sustainable yield. It is assumed that there will not be any substantial revisions between the preliminary
model of 2018 and final model in 2019 that would require revisions to work already done on historical
water budget and historical safe yield. We will wait for the final model to conduct simulations of future
conditions. If the final version of the USGS model is not available by July 2019, it will impact the schedule
and budget.
Modeling Future Conditionsodeling Future Conditions
M
Modeling Future ConditionsModeling Future Conditions
Dudek will incorporate the following simulations using the USGS numerical model to evaluate future
conditions and potential impacts from proposed projects. These simulations will satisfy the future
conditions evaluations required by SGMA.
1. Dudek will use one 50-year climate period to represent baseline climatic conditions for the basin.
This 50-year climatic period will be used to simulate future climatic conditions after applying
DWR’s climatic factors.
2. Dudek will conduct one baseline simulation that includes existing pumping and spreading.
3. Dudek will conduct two simulations to evaluate future projects against baseline conditions.
a. Each simulation may include one or more proposed projects concurrently to evaluate the
potential impact of their combined operations on groundwater conditions in the basin.

If the Yucaipa GSA requests additional predictive simulations to evaluate other climate change scenarios
or potential projects, than the scope of work and budget provided in this proposal will be amended and
presented for approval by the GSA.

Prepare Historical Water Budget
The historical water budget will be based on the data identified by the local agencies and provided to
Dudek during the 60-day period of data submittal. Data made available after the 60-day period of data
submittal will be held for incorporation in the 5-year updates.
Deliverables:eliverables:
Deliverables:Deliverables:
D
• Pre-draft historical water budget tables and figures for Yucaipa GSA review and comment
Technical Assessment of Monitoring Network
A memorandum will document the procedures used during the evaluation of the existing monitoring
program, and conclude with a discussion of expanding the network to be sufficient to meet SGMA

Page C-7
Yucaipa Sustainable Groundwater Management Agency - August 29, 2018 - Page 20 of 25