Transcript Proposed San Antonio Groundwater Basin Water Availability

Proposed
San Antonio Groundwater
Availability Project
Claudia Faunt and Matt Landon
California Water Science Center
U.S. Geological Survey
Stakeholders
•
•
•
•
•
•
Overlying Land Owners
Agricultural Interests
Los Alamos Community Service District
Vandenberg Air Force Base
Santa Barbara County Water Agency
United States Geological Survey
Benefits of the Study
• Develop a greater understanding of the hydrology of
the San Antonio Groundwater Basin
• Quantify the resources of aquifer
• Define groundwater availability with respect to
quantity and quality
• Predict potential effects of continued groundwater
overdraft
• Evaluate impacts of future groundwater
development on different parts of the basin under
differing climatic and cultural water use scenarios
Objectives
(1) refine the geohydrologic framework of the
San Antonio Creek Valley,
(2) quantify the hydrologic budget of the valley,
and
(3) develop hydrologic modeling tools to
evaluate, analyze, and manage the
groundwater resources.
Study Area
Project Tasks
(1) data compilation and new data acquisition,
• Increase groundwater level monitoring network
• Increase water quality sampling
• Drill dedicated observation wells
• Install stream gauges
(2) model development,
(3) analysis of water availability, and
(4) report preparation.
Note: Santa Barbara County will be instrumental in the
success of these tasks, particularly data acquisition.
Current Hydrologic Data
Map showing location of wells, generalized geology, and
selected groundwater-level hydrographs.
Multiple-Well
Monitoring
Sites
typical construction
Observation Well - Cuyama Example
Foothill Road
Multiple-Well
Monitoring
Site
Recent Water Levels - Cuyama
~40 ft of annual
water-level difference
From USGS Geohydrology Report, 2013
Stream Gauges - Cuyama Example
Downward Looking Radar
Continuous Stream Gauge:
Upper Cuyama River, Ventucopa (11136500)
Stream Gauge Installation:
Reyes Ranch, Santa Barbara Canyon,
Ventucopa (11136600)
Discharge Graphs for Stream Gauges
From USGS Geohydrology Report, 2013
Integrated Hydrologic and
Geohydrologic Model
• MODFLOW with Farm Processes
(Schmid and Hanson, 2005)
• Finite Difference Integrated
Hydrologic Model
• Three dimensional representation
of aquifer(s) and zones
• Simulates recharge,
evapotranspiration, flow to wells,
flow through different zones
From USGS Geologic Framework Report, 2013
Hydrologic Analysis –
Central Valley Example
Hydrologic Analysis –
Central Valley Example
Estimated Timeline
• Board of Supervisors hearing to approve
project: Late summer, 2014
• Project kickoff: October, 2014
• Existing data compilation: Fall, 2014
• Drill dedicated observation wells and auger
holes: 2015
• Expand water level and water quality
monitoring network: 2015 - 2018
• Testing of hydraulic properties: 2015-2016
• Groundwater model development: 2017
• Analysis and report, project complete: 2018