E KI T E CHNICAL PRE SE NT AT ION #3 CASTAC BASIN GSA BOARD - PowerPoint PPT Presentation

E KI T E CHNICAL PRE SE NT AT ION #3 CASTAC BASIN GSA BOARD OF DIRECTORS 4 JUNE 2019

OUT L INE 1. Data Gaps Assessment 2. Data Gathering Efforts 3. Groundwater Sustainability Plan (GSP) Development Update 4. Next Steps 2

1. DAT A GAPS ASSE SSME NT : Data Manage me nt Syste m (DMS) De ve lopme nt  Microsoft Access Database linked with a GIS geodatabase  Data used to initially populate:  Historical well location, construction, use, water level data and water quality from 2006-2008 analysis  Water level data from TRC wells through May 2018  Well location, construction, water level data and water quality data from SWRCB GeoTracker database  Well construction, water quality data, and Cuddy Creek peak streamflow from USGS  Pumping data (as counter units) from TRC wells through May 2018  Pumping data from public water systems for 2013 to 2015, as reported to Drinking Water Information Clearinghouse portal 3

1. DAT A GAPS ASSE SSME NT : DMS Status (as of 5/ 28/ 19) – Castac L ake Valle y Basin  113 Locations with Data  89 wells  1 surface water locations  21 others (soil borehole, piezometer, etc.)  Water levels ( 77 wells/sites)  Water quality ( 60 wells/sites)  Pumping data ( 10 wells) 4

1. DAT A GAPS ASSE SSME NT : DMS Status (as of 5/ 28/ 19) – Supple me ntal Data Data from other Basins will be used for water budget calculations and as supplemental information  128 Locations with Data  108 wells  9 surface water locations  11 others (borehole, piezometer, etc.)  Water levels ( 40 wells/sites)  Water quality ( 71 wells/sites)  Pumping data ( 4 wells) 5

1. DAT A GAPS ASSE SSME NT : Pr e liminar y Data Gaps (E ffor ts ar e ongoing)  Well construction, elevation, and type (needed for ~30 wells in Basin)  Water-level data (public water systems wells, upgradient-basin wells)  Water-quality data (TRC monitoring and irrigation wells, post-2008)  Pumping rates (public water systems wells, monthly pre-2013, units for pumping data from TRC pumping wells)  Castac Lake filling volumes, post-2007 (TRC)  Streamflow data (Cuddy Creek & Grapevine Creek, post-2007) 6

1. DAT A GAPS ASSE SSME NT : Plan for F illing Data Gaps Plan for Filling Data Gap Status Coordinate with GSA members to obtain pumping data Pumping data received from LCWD and units Flowmeter units & other data from TCWD/TRC pending Outreach to public water systems Krista Mutual transmitted data Additional outreach to school representatives needed Stakeholder survey and landowner data request form Complete distribution Coordinate with TCWD to collect additional water Post-2008 water chemistry data from TCWD/TRC quality samples, as needed pending Review options to collect additional streamflow and lake Obtained and compiled additional historical streamflow data data Examine water level differences in wells located on either Water level measurements received from LCWD side of the Basin boundary & potentially collect additional Analysis currently underway water level measurements, if needed 7

2. DAT A GAT HE RING E F F ORT S: Public Wate r Syste ms Data Re c e ive d  LCWD:  Pumping data for Jan 2013 – Dec 2018  Water level data for Sep 2012 – Sep 2018  Krista Mutual:  Pumping data for Sep 2010 – Feb 2018  Water level data for Jan 2010 – Dec 2019  Lake of the Woods MWC:  Well locations and logs 8

2. DAT A GAT HE RING E F F ORT S: L andowne r Data Re que sts  Castac Basin GSA sent out over 200 Landowner Data Request Forms in January 2019  We have received five responses to date (as of 5/28/2019) 9

2. DAT A GAT HE RING E F F ORT S: Sur ve y Re sponse s Approximate locations of responding stakeholders  Only one of the five stakeholders has a well  Two out of the five responding stakeholders have never heard of SGMA (one city resident, and one owner of undeveloped land)  Concerns expressed about groundwater management: “My only concern would be that those corporations,  organizations, water purveyors, water customers, and owner within the district be treated equitably with favor shown to no one particular interest over another.” “Over development in the mountain communities, with  such a limited water resource” “Conservation/sustainability”  10 10

2. DAT A GAT HE RING E F F ORT S: Additional Str e amflow Data Re c e ive d and Compile d  Cuddy Creek:  1980-2017 winter and summer peak flows from Kern County Floodplain Management  Stations at Lebec, Frazier Park, and Lake Grapevine Creek of the Woods  Grapevine Creek: Cuddy Creek  2000-2007 monthly streamflows  Various stations along Creek 11

3. GSP DE VE L OPME NT UPDAT E : Ke y SGMA r e quir e me nts  Notice and Communication (SCEP)  Data Management System (DMS)  Description of Plan Area  Hydrogeological Conceptual Model (HCM)  Groundwater Conditions Assessment  Water Budget  Sustainable Management Criteria (SMCs)  Monitoring Network  Projects & Management Actions (P&MAs) * 23-CCR Sections 352.6 , 354.8-20; www.water.ca.gov/groundwater/sgm/gsp.cfm 12

3. GSP DE VE L OPME NT UPDAT E : Plan Ar e a Ke y F indings  Basin encompasses 3,463 acres within the Tehachapi and San Emigdio Mountains at the southern end of Kern County  Potable consumption of groundwater in the Basin includes personal domestic well owners and public water systems 13

3. GSP DE VE L OPME NT UPDAT E : Plan Ar e a Ke y F indings Open Ground  Current Land Use:  Primarily grazing land  Some irrigated farmland acreage Urban Grazing  Some open spaces, mostly around the lake  Very little urban, rural residential, and open ground Rural Residential Lake Farmland Open Space 14

3. GSP DE VE L OPME NT UPDAT E : Plan Ar e a Ke y F indings Future Dedicated Conservation Easement  Tejon Mountain Village development will entail a major shift in land use Mountain Residential  Future Land Use Zoning: Open Area  Increase in residential areas  Decrease in open area and farmland Proposed Farmland  Added resort lands Village Mixed Use  Groundwater use not planned Resort 15

3. GSP DE VE L OPME NT UPDAT E : Plan Ar e a Ke y F indings  Density of wells per square mile based on DWR Well Completion Report records is very low  DWR data clearly are incomplete or miss-classified (this is common)  No public supply wells are identified within the Basin Well in the DMS 16

Hydrogeological 3. GSP DE VE L OPME NT UPDAT E : Conceptual Model Basin Se tting Ke y F indings  Basin is in a region of faulted, deformed, and uplifted igneous and metamorphic rocks. Grapevine  The Basin can be divided into Dryfield Canyon Canyon three areas:  Castac Lake portion  Dryfield Canyon portion  Grapevine Canyon Castac Lake 17

Hydrogeological 3. GSP DE VE L OPME NT UPDAT E : Conceptual Model Basin Se tting Ke y F indings  One Principal Aquifer with two “zones” Shallow (approx. 0 - 100 ft bgs) 1. Deep (approx. 100 - 350 ft bgs) 2.  Zones appear to be at least partially hydraulically connected  Water level data, aquifer pumping test results (2007), and water quality data indicate exchange of groundwater between zones 18 18

Hydrogeological 3. GSP DE VE L OPME NT UPDAT E : Conceptual Model Basin Se tting Ke y F indings  A series of upgradient groundwater basins and associated watersheds are sources of water inflows to the Castac Basin (Like a Connected Series of Gravel-Filled Tanks) Possible Groundwater Flow Cuddy Valley Restriction Basin Between Basins Cuddy Creek Cuddy Ranch ? Basin White Wolf and Cuddy Canyon Kern County Basin Subbasins Castac Lake Grapevine Basin Creek Grapevine Canyon 19 Figure is conceptual in nature. Relative fluxes or volumes are not implied.

3. GSP DE VE L OPME NT UPDAT E : Basin Se tting Ke y F indings Hydrogeological Conceptual Model  Recharge and Discharge Areas of Basin  Conceptual Water Flow Schematic 20

3. GSP DE VE L OPME NT UPDAT E : Basin Se tting Ke y F indings 2015 Spring Groundwater Elevations  Water level data within the Basin are very sparse  Preliminary rough piezometric surface contours (water level elevations) shown with 50-ft contour interval  Flow is generally from the Dryfield Canyon and Castac Lake portions towards Grapevine Creek 21

Long-T erm 3. GSP DE VE L OPME NT UPDAT E : Groundwater Trends Basin Se tting Ke y F indings  Example hydrograph from two TRC wells  Water-level declines in 1950s-1960s  No data 1970s to 2000s  Water-level recovery through 2002 flowing artesian wells 1999-2002   Decrease between 2000 and 2005  Recovery between 2005 and 2007 flowing artesian wells 2006-2007   Decrease 2007 onward Shallow well is dry since 2014  22

Long-T erm Groundwater 3. GSP DE VE L OPME NT UPDAT E : Trends, 2000 - 2018 Basin Se tting Ke y F indings 23