Page 82 - Yucaipa Sustainable Groundwater Management Agency - Yucaipa SGMA

2. Project Approach
Dudek’s approach to assisting the GSA in
developing a SGMA-compliant GSP submittal by
the January 22, 2019 deadline is outlined
following in accordance with the Scope Tasks
identified in the RFP. Dudek recommends,
however, that the GSA use the “DWR Guidance
Document for the Groundwater Sustainability
Plan (GSP) Annotated Outline” to structure the
Yucaipa GSP. Therefore, the following
descriptions include the chapter name in the
RFP and subsection name that corresponds to
the DWR guidance.
Task 1. USGS Groundwater Model
The USGS is currently developing a
hydrogeological numerical model of the Basin
using the USGS code GSFLOW. GSFLOW
includes two integrated model components to
simulate (1) watershed contributions to
recharge using the Precipitation Runoff
Modeling System and (2) groundwater flow
using MODFLOW-2005. USGS is in the process
of integrating the watershed model to simulate
recharge to the groundwater basin. The next
tasks for USGS are to calibrate the full
hydrogeological model and conduct water
availability analyses.
Dudek will work collaboratively with USGS to
use the model to identify data gaps, assess the
uncertainty in estimates of storage, and
evaluate sustainability indicators required
under SGMA. The model will also be used to
evaluate future impacts resulting from potential
projects in the Basin and climate change. The
USGS will prepare a report providing supporting
documentation for the modeling, and this report
will be included as an appendix to the GSP.
Dudek anticipates receiving the model input
files and supporting documentation from USGS.
It will be more efficient for Dudek to work
Develop Groundwater Sustainability Plan for the Yucaipa Basin Area
Yucaipa Sustainable Groundwater Management Agency - August 9, 2018 - Page 81 of 208
directly with the model in developing the GSP
while seeking input and support from USGS.
Task 2. Current and Historical
Groundwater Conditions
Dudek will work with the GSA member agencies
and USGS to collect all available historical and
current data derived from previous
hydrogeological investigations and the
development of the USGS numerical model.
Dudek, after consulting with the GSA member
agencies, will compile a list identifying all data
resources and make one request to obtain the
data. The goal is to collect all data up front so
we can effectively evaluate current and
historical conditions in the early stages of GSP
development. The data will be used to prepare
the “Current and Historical Groundwater
Conditions section of the “Plan Area and Basin
Setting” chapter of the GSP.
The data will be compiled, sorted, and
catalogued with a reference summary and
table of contents. The catalogue will be
structured such that additional data can be
easily added to it for ease of future data
management and use.
Dudek will review the existing data to assess
conformance with the pertinent sections of the
California Water Code and DWR’s Emergency
Regulations. The data will be evaluated to
identify data gaps, both spatially and
temporally, that will need to be addressed to
enhance our understanding of Basin conditions
and comply with the requirements of the GSP.
The data will be assessed for applicability
toward the six SGMA sustainability indicators,
including the data evaluation considerations
described in detail following.
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