1. Fox Canyon GMA Stream depletion
Fox Canyon GMA Stream depletion? GRAC Stream depletion workshop August 29, 2017
Bryan Bondy, PG, CHG
Contract GW MGR. – Calleguas MWD
Bondy Groundwater consulting, Inc.

2. Fox Canyon Groundwater Management agency
Kern County
Los Angeles County
Santa Barbara County
Ventura County
Fox Canyon GMA
Ventura
Oxnard
Thousand Oaks
Simi
Valley
River
Santa Clara
Calleguas Creek
Watershed

3. DO we have interconnected surface water?
§ Groundwater Conditions - (f) Identification of interconnected surface water systems within the basin and an estimate of the quantity and timing of depletions of those systems
§ 351. Definitions- (o) “Interconnected surface water” refers to surface water that is hydraulically connected at any point by a continuous saturated zone to the underlying aquifer and the overlying surface water is not completely depleted.

4. Fox Canyon gma PRIMARY SURFACE WATER BODIES
Coastal Wetlands

5. Oxnard Basin surface water not interconnected
Perched Zone – Not a “Principal Aquifer”
Vadose Zone

6. Las posas basin arroyo las posas is interconnected
Losing
Gaining
Losing
Shallow Aquifer
Methods:
Synoptic streamflow surveys in 2011 and 2012
Visual monitoring of streamflow terminus since 2012
Shallow aquifer monitoring wells drilled in 2013
Wastewater Treatment Plant
Other Surface Water Discharge

7. Surface water is the primary source of recharge to LPVB Eastern Mgmt
Surface water is the primary source of recharge to LPVB Eastern Mgmt. Area

8. Environmental beneficial use
Riparian vegetation transpires
~2,000 – 3,000 AFY
CA Gnatcatcher
SW Pond Turtle
Least Bell's
Vireo
Arroyo Chub

9. We have interconnected surface water Now what does it mean?
The surface water is principally wastewater and other discharges to the arroyo
SGMA does not distinguish between natural flow and discharges
GSA does not have authority to regulate quantity of discharges
Wastewater plant operators have SWRCB Division of Water Rights approval to divert for recycling

10. Wastewater plant flows and other discharges
Future
Worst
Case?
Draft

11. Minimum thresholds?
§ Minimum Thresholds – (c)(6) Depletions of Interconnected Surface Water. The minimum threshold for depletions of interconnected surface water shall be the rate or volume of surface water depletions caused by groundwater use that has adverse impacts on beneficial uses of the surface water and may lead to undesirable results.
Biggest risk of “depletion” is diversion for recycling
Very minimal extraction from shallow aquifer
Concern about future desalter projects that would pump shallow groundwater and potentially cause depletion

12. measurable objectives?
§ 351. Definitions- (s) “Measurable objectives” refer to specific, quantifiable goals for the maintenance or improvement of specified groundwater conditions that have been included in an adopted Plan to achieve the sustainability goal for the basin.
Consideration of setting MO for “aspirational goals”:
Not enforceable – does not trigger state intervention
Designed to encourage protection of riparian habitat

13. Monitoring?
§ Monitoring Network – (c)(6) Depletions of Interconnected Surface Water. Monitor surface water and groundwater, where interconnected surface water conditions exist, to characterize the spatial and temporal exchanges between surface water and groundwater, and to calibrate and apply the tools and methods necessary to calculate depletions of surface water caused by groundwater extractions.
How much effort should be put into monitoring given that current groundwater extractions do not appear to have a material linkage to depletion?
Expensive – who pays???
Dischargers? Shallow Desalter Project Proponents? Deep Aquifer Pumpers?

14. Focus on solutions
How can we protect riparian habitat AND mitigate future losses of surface water inflows to basin?

15. Arundo Removal
118
Moorpark 23

16. Arundo Removal Cost Initial Cost: $26.5 million
(good candidate for grant funding)

17. STORM WATER CAPTURE AND PERCOLATION USING Moorpark WWTP Percolation Ponds
Divert storm flow from arroyo into unused ponds for percolation
Subsurface infiltration pipes, pump, and pipes

18. STORM WATER CAPTURE PROJECT Moorpark WWTP Percolation Ponds Cost
Initial cost: $3.7 million

19. Contact: bondygroundwater@gmail.com 805-212-0484
Questions?
Contact:

20. EXTRA SLIDES

21. Historical Shallow Aquifer Groundwater Levels
Draft