through Improved Irrigation Efficiency in Pajaro Valley,...
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ResearchReport:
PotentialWaterSavingsthroughImprovedIrrigationEfficiency
inPajaroValley,California
Preparedfor:PajaroValleyWaterManagementAgency
by:VickiLin,
SamuelSandoval‐Solis,Ph.D.,BelizeA.Lane,
andJennaM.Rodriguez,M.S.
October2013
WATERMANAGEMENTRESEARCHLABORATORY
UniversityofCalifornia,DavisOneShieldAve.Dept.LAWR,Bldg.PES1111•Davis,CA95616ThisdocumentisavailableonlineviaWorldWideWebat
http://watermanagement.ucdavis.edu/e‐library/
Thispageinintentionallyleftblank
Recommendedcitation:Lin,V.,Sandoval‐Solis,S.,Lane,B.A.,andRodriguez,J.M.(2013).“Potential
WaterSavingsthroughImprovedIrrigationEfficiencyinPajaroValley,California,”FinalReport.
WaterManagementResearchGroup.UniversityofCaliforniaDavis.Davis,CA.
Availableonlineat:http://watermanagement.ucdavis.edu/e‐library/.
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ACKNOWLEDGMENTS
This work was completed as part of a research project (Research Agreement No.
201224936) with Pajaro Valley Water Management Agency. The assistance of Vicki Lin, a
student of University of California, Davis is greatly appreciated for compiling the data and
writingthepresentreport.
ABSTRACT
Water conservationnot onlyprovides short‐termbenefits for the environment, butmoreimportantly,itconstitutesalong‐terminvestmentforthefuture.PajaroValley,anagriculturalregion 90 miles south of San Francisco, is actively pursuing new strategies to improve thesustainabilityof theirwater resources. Wateruseefficiency is included in thevalley’sBasinManagement Plan (BMP) Update (Pajaro Valley Water Management Agency, 2013). Thisproject was developed in partnership with the Pajaro Valley Water Management Agency(PVWMA)toevaluate:(1)howmuchwatercouldbesavedthroughagriculturalconservation,and 2) the economic impact on the PVWMA and growers in Pajaro Valley. This projectestimatesthepotentialwatersavingsinPajaroValleybyapplying(a)aninterviewcampaignwith growers, (b) an evapotranspiration (ET) consultationwith experts, and (c) a statisticalanalysisofthecollecteddata.Throughgrowers’ interviews,datawasacquiredonquantityofwaterappliedtodifferentcropsandtheamountofmoneygrowersinvestincropproduction.To answer the water conservation savings question, the applied water and crop ET werecompared.Byconductinggrowerinterviews,theamountofwaterdifferentgrowersappliedtotheirvariousvegetableandberrycropswasdeterminedandthebehaviorofthestudysitewasappliedtotheentirevalley.Insummary,PajaroValleyhasthepotentialtosave4,600to5,100Acre‐Feetperyear(AF/year)ofwaterthroughconservation.
Twosetsofdatafrom2009and2011wereanalyzedtoestimatetheaverageappliedwatervolume per crop. The analysis focused on 2009 because it was a normal year in terms ofprecipitation andwater usage. LandusedataprovidedbyPVWMA for this year contained alargeacreage(16%)ofunknownagriculture.Thereisanestimatedtotalwatersavingsof4,600AF/year if anypotentialwater savings in the “unknownagriculture”areaaredisregarded. Ifthis area is considered and the unknown agriculture land is assumed to follow the samedistribution of crops as the rest of the valley, then the total potential water savings areestimatedas5,100AF/year.
WatersavingswillresultinadirectdecreaseinrevenueforPVWMArangingfrom$862,000to $951,000. To compensate for this loss in revenue, an increase in extraction fee rates(referredbyPVWMAasanaugmentationfee)wasconsidered.Thisactionwillaffectfarmers,especiallyvegetablecropgrowersinthecoastalzone.Coastalzonegrowerscurrentlyestimate$3,910/acrerevenuepergrowingseason.Ifwaterratesareincreasedby50%($105/AF),therevenueofvegetablecoastalgrowerswillbedecreasedby6.9%($271)pergrowingseason.Thisstrategywillaffect farmers, loweringtheirnetprofitoncrops.Growersofstrawberries,raspberries,blackberriesandnurserieshavealargerreturnperunitwaterapplied;therefore,increasedwaterfeeswillnotsignificantlyimpactthesegrowers.
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TABLEOFCONTENTS
Sectionpage
Acknowledgments ..................................................................................................................... ii
Abstract i
Table of Contents ........................................................................................................................ i
1. Introduction .........................................................................................................................3
1.1. Broad Vision........................................................................................................................................3
1.2. Scope of the Report.........................................................................................................................3
2. Background .........................................................................................................................4
2.1 Geography............................................................................................................................................4
2.2 Population.............................................................................................................................................5
2.3 Economic Activities..........................................................................................................................5
2.3.1 Agriculture............................................................................................................................................5
2.4 Pajaro Valley Water Management Agency (PVWMA)...................................................6
2.4.1 Objective...............................................................................................................................................7
2.5 Basin Management Plan (BMP)................................................................................................8
2.5.1 Development of the BMP..............................................................................................................8
2.6 Solutions................................................................................................................................................9
3. Methods
3.1. Framework.........................................................................................................................................11
3.2. Applied Water...................................................................................................................................11
3.3. Evapotranspiration.........................................................................................................................12
3.4. Field Campaign................................................................................................................................12
4. Data Sources .....................................................................................................................13
4.1. Applied Water...................................................................................................................................13
4.2. Field Campaign................................................................................................................................13
4.2.1. Interviews with Growers.....................................................................................................................13
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4.3. Evapotranspiration.........................................................................................................................13
4.4. Land Use Data.................................................................................................................................14
4.5. Groundwater Data..........................................................................................................................16
5. Water Budget Analysis ...................................................................................................18
5.1. Applied Water...................................................................................................................................18
5.1.1. Summary of Results.............................................................................................................................18
5.1.2. Acreage Factor........................................................................................................................................18
5.1.3. Water Use..................................................................................................................................................20
5.1.4. Applied Water: 2009 and 2011........................................................................................................21
6. Data Analysis to Estimate Potential Water Savings ...............................................22
6.1. Summary of Results for Potential Water Savings..........................................................22
6.2. Water Use Distribution Analysis and Water Savings....................................................23
6.2.1. Coastal and Inland Regions......................................................................................................25
6.3. Uncertainties: Unknown Ag. Use............................................................................................26
7. Economic Analysis ..........................................................................................................27
7.1. Introduction........................................................................................................................................27
7.2. Expected Economic Impact of Water Conservation......................................................27
7.3. Increase in Water Fees to Compensate Water Conservation..................................28
8. Conclusion .........................................................................................................................32
8.1. Limitations..........................................................................................................................................33
References 35
Appendix 36
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1. INTRODUCTION
1.1. BROADVISION
OfallwateronEarth,only2.5%isfreshwater.Theremaining97.5%consistsofsaltwater
whichistoosalineforhumanconsumptionorirrigationwithoutfurtherexpensivetreatment.
Of the freshwater, only 1.3% of this fraction consists of renewable surface water that is
readilyavailableforuse(U.S.GeologicalSurvey,2013).Thisamountofrenewablefreshwater
isaveryminisculeamountcomparedtothetotalamountofwaterthatexistsonEarth.Water
isalimitedresourceandonehastoputinthebesteffortinachievingwatersustainabilityto
maintain thisvital resource forboth currentand futuregenerations.Water sustainability is
definedasbeingabletoensurethereisenoughwatertomeettheneedsofhumanhealthand
theenvironmentinbothpresentandfuturetime.
Inordertoachievewatersustainability,effortscanbemadetomaximizewaterefficiency
and/orwaterconservation.Waterefficiencyinvolvesreducingtheamountofwaterrequired
foraparticularpurposeandfocusesonreducingwastedwater.Installinglow‐flowtoiletsor
fixing household leaks are examples of efficiency. The amount of water usage required is
lowered,butaperson’severydaybehaviorisnotaffectedbythechanges. Incontrast,water
conservation involves restricting water use and changing water demands, which affects a
person’s normal behavior. The prohibition of watering lawns or washing cars during a
droughtisanexampleofsuch.
This report focuses on improving water efficiency in the agricultural sector of Pajaro
Valley, California. To attain this goal, crop evapotranspiration datawas used to attain the
volumeofappliedwaterneededtoirrigatecertaincrops.Thesedatasetsarethencompared
toactualappliedwaternumbersfromfarmerstocheckforaccuracy.
1.2. SCOPEOFTHEREPORT
Thisreportdescribesmethods to improve irrigationefficiencywatermanagement in the
PajaroValley.ThePajaroValleyWaterManagementAgency(PVWMA)currentlyhasaBasin
Management Plan in place, but struggles to control groundwater overdraft and seawater
intrusion to their aquifers. Approximately 90% of water used within Pajaro Valley is
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groundwater(PVWMA,2013).Basinmodelingindicatesthatthecurrentbasinoverdraftisat
~10‐12TAF,1,500AF/Yandseawaterintrusioniscurrentlyat2,500AF/Y(PVWMA,2013).
ThemotivationforthisreportistoreduceoverdraftinthePajaroValleyaquifers,resultingin
lessseawaterrechargeinthesebasinsanddiminishedoverallwaterextraction.Theobjective
of this report is to explain the methods behind potential water savings in Pajaro Valley,
focusingstronglyonthewaterintensiveagriculturalsector.
2. BACKGROUND
2.1 GEOGRAPHY
The Pajaro Valley Watershed is roughly 1,300 square miles, extending over multiple
counties including Santa Cruz, Santa Clara, San Benito, and Monterey Counties (PVWMA,
2013).ThePVWMAmanagesanddeliverswatertoapproximately77,000acres(120square
miles) of this lower Pajaro River Watershed (Brian Lockwood, personal communication,
October24,2012).
Figure1.‐AreaswithinPVWMA’sJurisdiction.(Source:PajaroValleyWaterManagementAgency.http://www.pvwma.dst.ca.us/about‐pvwma/boundaries.php)
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ThelandisboundedbyMontereyCountytothenorth,SantaCruzCountytothesouth,the
SanAndreasFaulttotheeast,andthePacificOceantothewest(PVWMA,2013)
2.2 POPULATION
This report focuses on the people of Watsonville, California. This is due to
Watsonville’sstatusasamajorproduceroffruitsandvegetables.Watsonville’spopulationin
2010consistedof51,199people(UnitedStatesCensusBureau,2010).Ofthesecitizens,4,495
peopleworked in theagriculture, forestry, fishingandhunting,andmining industries. This
population represents 20.6%ofWatsonville’s population and contains amargin of error of
plusorminus3.2%(U.S.CensusBureau,2010).
Profitsearnedwithinthestrawberry,raspberry,blackberry,andlettucemarketaremajor
regional economic drivers. Many independent farmers in the Pajaro Valley work with
corporateagriculturalcompaniessuchasDriscoll’sandDoleBerries.
2.3 ECONOMICACTIVITIES
2.3.1 AGRICULTURE
TheeconomyofPajaroValleyislargelysustainedbyagriculture.Thevalleyranksfifth
in California in agricultural production and provides 90% of Santa Cruz County’s gross
agricultural income (Bannister et al., 2012). ManyPajaroValley farmers grow crops on
their own small farms to supply leading agricultural companies. Driscoll’s is one of the
largest suppliers of berries and can be found year round in over 61 retail locations
throughout the United States (Driscoll’s, 2013). Watsonville is a major supplier of
Driscoll’s berries, with annual production starting from the beginning of April to the
middleofDecember(Driscoll’s,2013).
Agriculture uses roughly 80%of thewater that is pumped from the basin (PVWMA,
2013). As mentioned earlier, the PVWMA manages 77,000 acres of land in the Pajaro
Valley. Table1‐1shows total agriculturalacreageuse in2012 tobe28,367acres in the
PajaroValley.WithinPajaroValley,41%oftotallandisusedexclusivelyforagriculture.
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Such a high offset of land for agricultural use shows promising results for potential
watersavingsintheagriculturalsector.
Table1.‐SummaryofLandUseinPajaroValley.(AdoptedfromPVWMA,2013).
2.4 PAJAROVALLEYWATERMANAGEMENTAGENCY(PVWMA)
The PVWMA is a state‐chartered water committee led by a seven member Board of
Directors. The PVWMA Board holds monthly meetings to vote on decisions and oversee
project development. The agendas of these meetings includes finalizing contracts with
engineering firms, planning projects under CEQA guidelines, and addressing community
input. The Board of Directors established Ad Hoc BMP Update Committee and directed
agencystafftoworkwiththeCommitteetodevelopanUpdatetoitsBasinManagementPlan
that would solve the water resources problems of groundwater overdraft and seawater
intrusion.TheCommitteeconsistedoftwentyonemembersrepresentingentitiesconsisting
of the PVWMA, local county representatives, stakeholders, environmentalists, farmers, and
residents (PVWMA, 2013). The main objective for the creation of this committee was to
includecommunityinputintotheBMPUpdateprocess.
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Figure2.–BMPCommitteeResourcesandReportingStructure.(AdoptedfromPVWMA,2013).
2.4.1 OBJECTIVE
ThePVWMAwascharteredto:
1)Sustainablybalancewatersuppliesinanefficientandeffectivemanner.
2)Managewatersuppliestoreducecontinuingoverdraftofgroundwater.
3)Provideandensurewatersupplyforcurrentandfutureneedswithintheirboundaries.
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2.5 BASINMANAGEMENTPLAN(BMP)
The PVWMA’s Basin Management Plan (BMP) was first adopted in 1994 and has been
updatedandredraftedthreetimeseversince(PVWMA,2013).
ThePVWMArecentlyupdatedtheirBasinManagementPlan(BMP)in2012toaddressthe
overdraftandsaltwaterintrusionproblemsinthebasin.ThegoalsoftheBMPstemfromthe
objectivesofthePVWMA.Theyareto:
1.Sustainablybalancewaterdemandtomatch thewatersupplywithcurrentand future
waterdemands.
2.Preventsaltwaterintrusionintoaquifers—aconcurringproblemsince1953.
3.Developawaterportfolioandconstructstrategiestoguaranteewaterqualityandsupply
forfuturegenerations.
Proposed solutions for their goals include management strategies that include water
conservation, switching to alternative water sources, and developing new water projects
(PVWMA,2013).
AllthesestrategiesgothroughalongreviewprocessbythePVWMAincludinginputfrom
watermanagers,stakeholders,andthecommunity.
2.5.1 DEVELOPMENTOFTHEBMP
TheAdHocBMPUpdate Committeewas largely responsible for the development of the
BMP. The development of the plan was balanced by input from a modeling committee, a
water quality and operations committee, and the community. They met for 18 months
undergoingthefollowingprocesstoyieldtheirfinalresults:
Figure3.‐The2012BMPSelectionProcess.(AdoptedfromPVWMA,2013.)
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The project screening process beganwith 44 projects that were analyzed based on the
cost, implementation issues, and overlapwith different projects regardingwater source or
location(PVWMA,2013). Allbut14projectswereeliminatedandmoved into theportfolio
development phase. These 14 projects then underwent a hydrologic modeling process to
determinethebestwaterportfolio.
2.6 SOLUTIONS
SeveralstrategieswereconsideredbytheBMPtoreduceoverdraft.Theyaredividedinto
threecategories:
1.Developnewsupplies
2.Optimizetheuseofexistingsupplies
3.Usewatermoreefficiently
TheBMPupdatefinalizedsevenprojectsandprogramsthattheyseektoimplement:
1)Conservation
2)Increasednighttimerecycledwaterdemand
3)Increasedrecycledwaterstorageattreatmentplant
4)HarkinsSloughrechargefacilitiesupgrades
5)WatsonvilleSloughandNorthDunesRechargeBasin
6)CollegeLakewithinlandpipelinetoCoastalDistributionsystem(CDS)
7)MurphyCrossingwithrechargebasins
These strategies are classified according to their different types: groundwater, surface
water,recycledwater,demandmanagement,seawater,andinfrastructure.Projects(1‐2)are
demandmanagementprograms thatmaximize theuseof existing facilities. Project (3) is a
recycled water alternative which focuses on maximizing the use of recycled water by
increasing the size of the recycled water storage facility. Projects (4‐7) are surface water
alternatives that involve constructing new infrastructure to divert water from the Pajaro
River, theWatsonvilleSlough,HarkinsSlough, andCollegeLake into rechargebasinsor the
CoastalDistributionSystemduringcertainmonths(PVWMA,2013). Theseprojectsallhave
animplementationtimebetween0to20yearsifapprovedafterCEQAhearings.
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Figure4.‐DistributionofWaterSavingsinPajaroValley.(AdoptedfromPVWMA,2013).
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3. METHODS
3.1. FRAMEWORK
Two data sets were used to estimate potential agricultural water savings in this study:
appliedwaterandevapotranspiration(ET)data.Thesenumberswerethencomparedagainst
theempiricaldataprovidedbygrowerstofurtherevaluatetherelationshipbetweenapplied
waterandevapotranspiration.
Figure5.‐FrameworkBehindPotentialWaterSavings.
3.2. APPLIEDWATER
Appliedwater(AW)wascalculatedbydividingthevolumeofwaterinacre‐feet(AF)wells
producedbywellsbytheamountof landuse(acres)thiswaterwasappliedover. Applied
wateristhusthevolumeofwaterappliedpercroparea.
…Eq.[1]
Water Savings
2) ET
3) Growers' Interviews
1) Applied Water
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Datawasanalyzedfor54differentfarmpropertiesintwodifferentyears—anormalyear
(2009) and awet year (2011). The calculatedAWnumberswere later combinedwith the
landusedatatocalculatewaterusefordifferentcropsthroughaweightedaverage.
3.3. EVAPOTRANSPIRATION
Evapotranspiration(ET)isaphysicalprocesswherebythetransferofwaterfromlandto
the atmosphere is facilitated simultaneously by evaporation and transpiration. Water is
transferred fromsoil to theatmosphere throughevaporationand fromaplant’s stomata to
theatmospherebytranspiration.
Crop evapotranspiration (ETc) is the ET values of crops under standard conditions.
Standard conditions include healthy,well‐fertilized, andwell‐watered crops grown in large
fieldsthatallowthemtoreachtheirmaximumcropproduction(Allenetal.,1998).
Evapotranspirationvalueswereprovidedformultiplecropsforbothwetanddryyearsby
irrigation andwater resources expert and farmadvisor,Michael Cahn. Cropshad lowerET
valuesduringthewetyearandhigherETvalueduringthedryyear.
3.4. FIELDCAMPAIGN
A field campaign was conducted to compare calculated AW numbers and ET values.
FarmerswereaskedtosharetheirAWvaluesandtheamountofmoneytheyhadinvestedin
production.AWwasgreaterduringthenormalyearthanthewetyear.
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4. DATASOURCES
Two different data sets provided by the PVWMA were compared in this study: well
production(AF)andlanduse(acres).Thesedatawereusedtocalculatethevolumeofwater
applied during 2009 (a normal groundwater extraction year) and 2011 (a below average
groundwaterextractionyear). Thisproject focusedon2009because itsdata isclosetothe
fiveyeargroundwaterextractionaverageinPajaroValley.
4.1. APPLIEDWATER
Metered well data was provided by the PVWMA for 888 production wells and 46
deliveredwaterturnoutconnectionsfortheyears2009and2011.
4.2. FIELDCAMPAIGN
4.2.1.INTERVIEWSWITHGROWERS
Interviewswere conductedwith twentydifferent farmers in thePajaroValley. Farmers
were asked to share their AW values and the amount ofmoney they had invested in crop
production. A wide data sample of crops including nurseries (5), strawberries (4),
raspberries and blackberries (3), blueberries, vines and grapes, artichokes, apples, and
vegetablerowcrops(6)wascollected.
4.3. EVAPOTRANSPIRATION
Evapotranspiration (ET) valueswere provided by irrigation andwater resources expert
and farm advisor, Michael Cahn for vegetable row crops, strawberries, raspberries, and
blackberries. Values were given for both wet and dry years. Dr. Jean Caron of Laval
University, confirmed these values conducting his own independent research. This project
focuses on the aforementioned crops because they represent 75% of the total acreage of
plantsgrowninthevalley.
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Table2.–EvapotranspirationValuesforMultipleCrops
ET (AFY/acre) Crops Lower Upper
Vegetables Row Crops (lettuce, Celery, Zucchini, etc.) 2.20 2.60 Strawberries 1.90 2.20 Raspberries 1.80 2.10 Blackberries 1.90 2.20
AFY – Acre‐feet per year
4.4. LANDUSEDATA
The land use data was collected through field campaigns of PVWMA. Figure 6 and 7
displaysthedistributionofcropsfor2009and2011.
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Figure6.‐2009PajaroValleyLandUseData.(AdoptedfromPVWMA,2013).
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Figure7.‐2011PajaroValleyLandUseData.(AdoptedfromPVWMA,2013).
4.5. GROUNDWATERDATA
Groundwaterdatawascollectedusing flowmeters installedandmaintainedbyPVWMA.
ThisdataisreferredtobyPVWMAas“productionwell”datameaningthesewellsareusedto
extractwater from theground. Meteredproductiondata is kept in adatabasebyPVWMA.
This information also includes Coastal Distribution System called “turn outs data,” which
referstopipeconnectionstotheCoastalDistributionSystem(CDS)installedbyPVWMA.The
CDSistheinfrastructurethroughwhichwaterdeliveriesforirrigationpurposesaremadeto
growers in the impacted coastal area. Sources of delivered water include recycled water,
groundwater and water recovered from the PVWMA’s Managed Aquifer Recharge and
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RecoveryFacility.Figure8showsthedistributionofproductionwellsandturnoutsinPajaro
Valley.
Figure8.‐PajaroValleymeteredwellandturnoutlocations.(AdoptedfromPVWMA,
2013.)
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5. WATERBUDGETANALYSIS
5.1. APPLIEDWATER
5.1.1.SUMMARYOFRESULTS
Thissectionexplains thewaterbudgetcreatedtoestimate theamountofwaterused for
eachcropcategoryandthedistributionofappliedwaterwithineachcrop.Table3showsthe
summaryofresultsfor2009. Insummary,totalappliedwateristheproductoftheacreage
(Column1,Table9)ofeachcroptimestheaverageAW(AF/acre)(Column3,Table9)usedon
eachparticularcrop.ThesevaluesweremultipliedbyanAcreageFactor(Column4,Table9),
consideringonlyafractionofthesurfaceareaonapropertyisusedforcropproduction.
Table3.‐Summaryofappliedwater(AW)resultsfor2009.
CalendarYear:2009 Wat.Use Acreage AppliedWaterLandUseType Acres (%) (AF/acre) Factor (acre‐feet)Fallow 2,767 10% VegetablesRowCrops1 6,318 22% 2.67 0.80 13,513Strawberries1 7,068 25% 2.36 0.80 13,338Raspberries,Blackberries1 3,655 13% 2.34 0.80 6,832Blueberries3 0 0% Vines/Grapes3 27 0% 2.68 0.80 58Artichokes2 180 1% 1.50 0.80 215Deciduous(AppleOrchards)1 1,530 5% 0.52 0.80 639Nurseries/Flower/SubtropicalPlants2 1,397 5% 4.21 0.13 765Other1 788 3% 1.93 0.80 1,215UnknownAg.Use3 4,569 16% 2.68 0.80 9,794Total 28,299 100% 2.05 0.80 46,370Notes:1–AverageappliedwaterperacrecalculatedfromtheproductionwellandlandusedataprovidedbyPVWMA.2.‐AppliedwaterprovidedbyexpertsandPajaroValleygrowers.3.‐Appliedwaterderivedoncetherestofthecropswerecalculated.
5.1.2.ACREAGEFACTOR
Theacreagefactor(AF)isestimatedasaratiooftheacreageofcropproductiontothetotal
acreage of land on the property, and as thus, is critical in quantifying appliedwater to the
surveyedarea.ThetotalacreageofmultiplepropertieswasprovidedbythePVWMAthrough
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their land use survey. However, assuming growers grew crops on every acre of their
property,theamountofappliedwaterusedwouldbeunderestimatedandthepotentialwater
savings would be less realistic and more difficult to attain. In order to determine the
productiveareasonaproperty,polygonsweredrawnfromaerialfootageofthesurveyedarea
usingArcGIS.Byusingaerialfootage,theproductionareaofcertainpropertieswasoutlined.
ArcGISwasusedtoestimatetheacreageoflandthatwasusedforproduction.
Figure10.‐AcreageFactorSampleCalculation.
InFigure10, theacreage factor(AF)ofstrawberrieswasestimatedasaratioofacresof
strawberryproductionover the totalacresof landon theproperty. Strawberryproduction
areawas already provided by growers. The total land areawas determined by drawing a
polygon from aerial footage in the area provided in the Land Use survey. After acreage
calculations,thetotalareaofthepropertyintheLandUsesurveywasdeterminedtobe14.6
acres.AnAFof0.77wascalculatedafterdividingtheacresofstrawberryproductionoverthe
total acres of property. This number means roughly 80% of the property is used for
strawberryproduction.
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Table4.‐SampleSizesofWellProductionData.
*ThesevalueswereprovidedbytheempiricalknowledgeofPajaroValleygrowers
Fifty‐fourdifferentpropertieswereassessedinthisproject.Basedonfieldcropdatainthe
land use survey, the average AF of these 54 properties was calculated to be about 0.80.
Therefore, it is assumed that farmers allocate80%of their totalproperty acreage to crops.
Nurseriesareaspecialcase,carryinganAFof0.13duetorequirementsforonlyaverysmall,
concentrated area of production. There were not enough interviews conducted for
blueberries, vines and grapes, artichokes, and nurseries so we used values based on the
expertiseofgrowers.
5.1.3.WATERUSE
AsstatedinEquation[1],WellproductiondataiscriticalincalculatingAW.This
datawasprovidedbythePVWMA. Theagencyshareddataregarding888productionwells
includingthepropertiesthatwithdrewwaterfromthesewellsandthevolumeofwellwater
used.Theproductiveacreageoneachofthe54sampledpropertieswerecalculatedusingthe
aerial methods described in the previous section. All farmers in the surveyed area were
assumedtoexhibitthesamebehaviorasthe54farmersselectedforanalysis.TheWaterUse
(Table 5)was estimated as an average of differentwater use samples thatwere calculated
usingtheprocedureexplainedinsection5.1.
Crop SampleSizeVegetablesRowCrops(lettuce,Celery,Zucchini,etc.) 12Strawberries 13Raspberries,Blackberries 14Blueberries* 1Vines/Grapes* 1Artichokes* 2Deciduous(AppleOrchards) 15Nurseries/Flower/SubtropicalPlants* 5Other ‐‐‐
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Table5.–2009AppliedWaterData.
CalendarYear:2009 Wat.UseLandUseType (AF/acre)Fallow VegetablesRowCrops(lettuce,Celery,Zucchini,etc.) 2.67Strawberries 2.36Raspberries,Blackberries 2.34Blueberries Vines/Grapes 2.68Artichokes 1.50Deciduous(AppleOrchards) 0.52Nurseries/Flower/SubtropicalPlants 4.21Other 1.93UnknownAg.Use 2.68Total 2.05
5.1.4.APPLIEDWATER:2009AND2011
Table6.–AppliedWaterandEvapotranspirationDataforNormal(2009)andLow
(2011)GroundwaterExtractionYears.
Normal(2009) Low(2011)
Crop ET AW ET AWFallowVegetableRowCrops 2.58 2.67 2.17 2.24Strawberries 2.23 2.36 1.89 2.24Raspberries/Blackberries 2.25 2.34 1.88 2.03Blueberries* 1.75 1.75Artichokes* 1.50 1.50Deciduous(AppleOrchards)* 0.50* 0.52 0.35* 0.34Nurseries/Flowers/SubtropicalPlants* 4.00* 4.21 3.85* 3.85Units‐Acre‐FeetperYear(AFY)*Grower
AWvaluewasgroundgreaterthantheETvalueexceptfordeciduouscropsduringthewet
year. ThegoalistoreducetheamountofAWtotherecommendedETvalueforallcropsin
ordertoimprovewaterefficiency.
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6. DATAANALYSISTOESTIMATEPOTENTIALWATERSAVINGS
6.1. SUMMARYOFRESULTSFORPOTENTIALWATERSAVINGS
Thegoalofthisprojectwastodeterminetheamountofwaterthatcanpotentiallybesaved
per acre foot of production land. This required calculating a target value of appliedwater
basedonacrop’sETvalue. TheETvalue indicatesoptimumwateramountsthatshouldbe
appliedinorderforthewatertobecompletelybeneficial.Applyinganymorewaterthanthe
ETvalueisconsideredwastefulbecausetheexcesswaterisnottakenupbythecrops.After
consideringETvalues inourcalculations, therewasa totalwatersavingsof4,600 to5,100
acre feet per year for the land surveyed area. This is a big improvement, with an average
water use efficiency of 91% in the production area. Theprevious resultswere obtainedby
conductingadistributionanalysisforeachcrop.Thisprocessessentiallyinvolvedestimating
howmanyfarmersusedmorewaterthanrequiredbyacrop’sET.
Table7.–PotentialWaterSavings:LowerEnd.
CalendarYear:2009 Wat.Use AppliedWater WaterSavings(AFY)
LandUseType Acres (AF/acre) (acre‐feet) Coastal Inland Total
Fallow 2,767
VegetableRowCrops1 7,219 2.67 15,441 636 1,089 1,725
Strawberries1 8,076 2.36 15,242 948 1,114 2,063Raspberries,Blackberries1 4,171 2.34 7,796 ‐‐‐ 596 596
Blueberries 0
Vines/Grapes3 27 3.96 86
Artichokes2 180 1.50 215 Deciduous(AppleOrchards)1
2,129 0.52 889 ‐‐‐ 189 189
Nurseries/Flowers/SubtropicalPlants2
1,463 4.21 801 13 42 54
Other1 788 1.93 1,215
UnknownAg.Use3 1,480 3.96 4,684 0 0 0
Total 28,300 2.05 46,370 1,597 3,030 4,627Notes:1.‐AverageappliedwaterperacrecalculatedfromwellproductionandlandusedataprovidedbyPVWMA.2.‐AppliedwaterprovidedbyexpertsandPajaroValleygrowers.
‐23‐
3.‐AppliedwaterderivedoncetheAWvaluesof(1)and(2)werecalculated.
Table8.–PotentialWaterSavings:UpperEnd.
CalendarYear:2009 Wat.Use AppliedWater Wat.Savings(AFY)LandUseType Acres (AF/acre) (acre‐feet) Coastal Inland TotalFallow 2,767VegetableRowCrops1 7,219 2.67 15,441 636 1,089 1,725Strawberries1 8,076 2.36 15,242 948 1,114 2,063Raspberries,Blackberries1 4,171 2.34 7,796 ‐‐‐ 596 596
Blueberries 0Vines/Grapes3 27 3.96 86Artichokes2 180 1.50 215Deciduous(AppleOrchards)1 2,129 0.52 889 ‐‐‐ 189 189
Nurseries/Flowers/SubtropicalPlants2
1,463 4.21 801 13 42 54
Other1 788 1.93 1,215UnknownAg.Use3 1,480 3.96 4,684 196 272 468
Total 28,300 2.47 46,370 1,793 3,302 5,095Notes:1.‐AverageappliedwaterperacrecalculatedfromwellproductionandlandusedataprovidedbyPVWMA.2.‐AppliedwaterprovidedbyexpertsandPajaroValleygrowers.3.‐AppliedwaterderivedoncetheAWvaluesof(1)and(2)werecalculated.
6.2. WATERUSEDISTRIBUTIONANALYSISANDWATERSAVINGS
Inordertoestimatewaterusedistributionthroughoutthevalley,thewaterusedataofthe
twelvesampledpropertieswasappliedtotheentiresurveyedarea.Forvegetablerowcrops,
farmersappliedwaterrangingfrom2.00to3.83AFor24to45inchesperacre.Intervalsof
twoinches/acrewereusedtobinfarmersintoseparatewaterusegroups.
‐24‐
Table9.–VegetableRowCropData.
Theredlineindicatesthetargetvolumeofwaterforvegetablegrowers.
AsamplecalculationforthetotalacreageofvegetablerowcropsshowinTable9. Three
farmersapplied24inchesofwaterperacreofland.Sincethesethreefarmerswereoutofa
sampleoftwelve,25%ofall farmersinthesurveyedareawereassumedtohaveapplied24
inchesofwaterperacreofland.Thefrequencyofwaterusewasmultipliedbythetotalland
area(7219acres)tocalculatehowmuchacreagereceivedaspecificrangeofwaterperacre
feet.
Column7fromTable9providesanestimationoftotalpotentialwatersavings.In
ordertodothis,theexactamountofwaterrequiredforcropstobeputtobeneficialusewas
calculated and subtracted from thepreviously calculatedAWvalue in column6of Table 9.
Thewaterusage (Column5)most significantly influences theoutcomes of the calculations.
Forvegetable crops, farmersused2.08 to3.83 feet ofwaterper acre foot. ET values from
Cahn(personalcommunication)indicatethatapplying2.58AFofwaterduringanormalyear
issufficientforthecroptothrive.AsseeninTable9,therearenowatersavingsforfarmers
abovetheredlinebecausetheyarealreadyapplyingwaterbelowtheETvalue.
‐25‐
6.2.1. COASTALANDINLANDREGIONS
The crop acreage for inland and coastal zones was provided by the land use data. All
farmers in these regions were assumed to display the same water use distribution as the
farmerssampled,asexplainedintheprevioussection.Weestimatedhowmanyacresofland
were using more water than the suggested ET value for both coastal and inland regions.
Potential water savings were estimated based on the difference between the pre‐adjusted
waterusevaluesandtheadjustedETvaluesacrosstheacreagesofcropsnotmeetingtheET
value.
Table10.–LowerBoundVegetableRowCropWaterSavings.
Coastal Inland
(acre) (acre)
2146 5073 Water Savings
Coastal Inland
Inches Frequency(%) Acreage Acreage Wat. Savings Wat. Savings
24 25% 537 1043
26 8% 179 348
28 17% 358 695
30 8% 179 348
32 0% 0 0 0 0
34 0% 0 0 0 0
36 8% 179 348 60 116
38 17% 358 695 167 324
40 8% 179 348 107 209
42 0% 0 0 0 0
44 0% 0 0 0 0
45 8% 179 348 179 348
100% 2146 4171 513 996
‐26‐
Table11.–UpperBoundVegetableRowCropWaterSavings.
Coastal Inland
(acre) (acre) Unknown Ag.
Coastal Inland Coastal Inland
Inches Frequency(%) Acreage AcreageWat.
Savings Wat.
Savings Wat.
Savings Wat.
Savings
25 25% 537 1043
27 8% 179 348
29 17% 358 695
31 8% 179 348
33 0% 0 0 0 0 0 0
35 0% 0 0 0 0 0 0
37 8% 179 348 60 116 40 11
39 17% 358 695 167 324 40 30
41 8% 179 348 107 209 26 19
43 0% 0 0 0 0 0 0
45 0% 0 0 0 0 0 0
47 8% 179 348 179 348 43 32
100% 2146 4171 513 996 123 92
Fromourvegetablecropsample, itcanbeseenthatthere isahigherpotential forwater
savingsininlandregionsversusthecoastalregions.Thispatternisconsistentwiththerestof
thecropssampled.Twodatasetswereusedtoaddressthelanduseuncertaintiesregarding
unspecifiedcropsgrowninsomeareasofthelandusesurvey.
6.3. UNCERTAINTIES:UNKNOWNAG.USE
In the 2009 landuse data, there is a crop category labeled as “UnknownAgUse”which
accounts for 16% of the total crop acreage in the surveyed area. The PVWMA did not
determine some specific crop varieties while obtaining the data for this land survey.
Discountingtheacreagesofunknownagricultureuse,thewatersavingsinPajaroValleyare
estimatedtobe4,600AF. However, if this16%of landwasaccountedforand,cropsinthe
unknownagriculturecategorywereassumedtobedistributedinthesamepercentageasthe
restofthelandinthevalley,thereisanestimatedwatersavingsof5,100AF.
‐27‐
7. ECONOMICANALYSIS
7.1. INTRODUCTION
Theobjectiveofthissectionistopresenttheeconomicimpactsof:
1) SavingwaterinPajaroValleyandtheexpectedreductioninrevenueforPVWMAasaresult
ofwaterconservation
2) RaisingwaterextractionfeesinPajaroValley
7.2. EXPECTEDECONOMICIMPACTOFWATERCONSERVATION
Accordingtothisreport,thePVWMAhasthepotentialtosavebetween4,600and5,100AF
ofwaterperyearbypracticingwaterconservation.Thishasadirectimpactontheagencyas
theywilllosetheannualrevenuethatwouldotherwisebecollectedifconservationmeasures
werenotputintoplace.Thislossofrevenuewillbeamajorissueastheagencyisalreadyin
debt.
PVWMA charges an augmentation fee to those who pumped water within the agency’s
boundaries.ForFiscalYear2013/2014,theaugmentationfeeis$174AFforinlandareasand
$210AFforcoastalzones.(PVWMA,2013).Thefarmersinterviewedalsopresentedaverage
electricity bills of $110 per AF of water paid to Pacific Gas & Electric Company (PG&E).
Therefore, pumping water from any well costs $284/AF in inland areas and $320/AF in
coastalzones.
Assuming the PVWMA maintains its augmentation fee of $174 and $210 per AF, the
PVWMAwould losebetween$862,000and$951,000 in revenueperyear.Thesevaluesare
basedonourlowerandupperboundwatersavingsestimates.TheBMPestimatesthelossin
revenuetobeamaximumof$1,000,000peryear,avaluesimilartoourestimation(PVWMA,
2013).Thisdocumentalsopredictsanannualoperationandmaintenancecostof$250,000to
$300,000forthefirstthreetofiveyearsoftheconservationprogram.Thesewatercostsand
revenuelosesarenotadjustedforinflation,butitisassumedtheywillincreaseasthePVWMA
increasesitsrateseveryJulybasedontheConsumerPriceIndex(PVWMA,2013).
‐28‐
7.3. INCREASEINWATERFEESTOCOMPENSATEWATERCONSERVATION
To compensate for the $862,000 to $951,000 yearly loss in revenue from water
conservation, one strategy is to raise extraction fees. This strategy will affect farmers by
loweringthenetprofitoncrops.
Table12.–RevenueperCropPriortoRateIncreases
Profit Inland Coast
Inland & Coastal* Investment** Net Profit Investment** Net Profit
($) ($) per AF ($) per AF ($) per AF ($) per AF
Vegetables $10,000 $6,000 $4,000 $6,090 $3,910
Strawberries $68,000 $27,500 $40,500 $27,583 $40,417
Raspberries $59,000 $23,110 $35,890 $23,182 $35,818
Blackberries $59,000 $25,000 $34,000 $25,082 $33,918
Nurseries $205,000 $75,500 $129,500 $75,647 $129,353
*Profit.Averageprofitofbothcoastalandinlandregions.Theprofitofcropsperacrewereobtainedthroughthe2012Ag.Commissionerreport(MontereyCountyAgriculturalCommissioner,2012).
**Investment.ThisdatawascollectedthroughinterviewswithgrowersinPajaroValley.
Table12showstheaverageamountofmoneyfarmersinvestintheircrops,theirprofits,
and theirnetprofit. The investmentdatawasgathered throughgrower interviewsand the
profits were calculated using data from Monterey County’s 2012 Crop Report (Monterey
CountyAgriculturalCommissioner,2012).Subtractinginvestmentsfromprofitsprovidedthe
netprofitobtainedfromdifferentcropsperAFofwater.
‐29‐
Figure11.‐(Inlandzone)relationshipbetweenthecostofwaterandtheproportionoftotal
cropinvestmentspentonwaterforkeycroptypes.
0%
5%
10%
15%
20%
25%
30%
$174 $218 $261 $305 $348 $392 $435 $479 $522
Cost of Water/Total Investment
Cost of Water ($ per AF)
Vegetables
Nurseries‐ Green Houses
Raspberries
Blackberries
Strawberries
Δ(0%) Δ(25%) Δ(50%) Δ(75%) Δ(100%) Δ(125%) Δ(150%) Δ(175%) Δ(200%)
‐30‐
Figure12.‐(Coastalzone)relationshipbetweenthecostofwaterandtheproportionof
totalcropinvestmentspentonwaterforkeycroptypes.
Figures11and12showtherelationshipbetweenthecostofwaterandtheproportionof
totalcropinvestmentspentonwaterforkeycroptypes. Resultssuggestthatthenetprofit
per AF depends heavily on the type of crop being produced. Vegetables have a return of
$4,000perAFofwaterasopposedtonurserieswithareturnof$129,000perAF.Vegetable
growerswillbethemostsignificantlyimpactedbytheincreaseofwaterratesbecausetheir
investment per AF ofwaterwill increase, substantially lowering their total net profits. For
instance, foracoastal farmer, if thewaterextractionfee is increasedby50%(from$210to
$315), the cost of water relative to the total investment cost will increase from 13.6% to
18.0%.Inotherwords,thewatercostwillincreasefrom$827to$1,098peracreforthecrop
season. Strawberries, raspberries, blackberries will be moderately affected by the rate
increase,andnurserieswillonlyseeaminordecreaseintheirnetprofits.
0%
5%
10%
15%
20%
25%
30%
35%
$210 $263 $315 $368 $420 $473 $525 $578 $630
Cost of Water/ Total Investment
Cost of Water ($ per AF)
Vegetables
Nurseries‐ Green Houses
Raspberries
Blackberries
Strawberries
Δ(0%) Δ(25%) Δ(50%) Δ(75%) Δ(100%) Δ(125%) Δ(150%) Δ(175%) Δ(200%)
‐31‐
Table13.–IncreaseinInvestmentCostswithRateIncreases(Inland).
Investment Applied Water
$/AF Δ(50%) Δ(75%) Δ(100%) Δ(150%) Δ(200%)
($) (AF/acre) $174 $261 $305 $348 $435 $522
Vegetables $6,000 2.6 IIC 12.2% 16.0% 17.8% 19.7% 23.3% 27.2%
DV $0 $958 $1071 $1183 $1408 $1633
Strawberries $27,500 2.4 IIC 2.4% 3.2% 3.6% 3.9% 4.7% 5.4%
DV $0 $875 $978 $1080 $1286 $1491
Raspberries $23,100 2.3 IIC 2.9% 3.8% 4.2% 4.6% 5.5% 6.4%
DV $0 $867 $968 $1070 $1273 $1477
Blackberries $25,000 2.3 IIC 2.7% 3.5% 3.9% 4.3% 5.1% 5.9%
DV $0 $867 $968 $1070 $1273 $1477
Nurseries $75,500 4.2 IIC 1.6% 2.1% 2.3% 2.5% 3.0% 3.5%
DV $0 $1558 $1741 $1924 $2289 $2654
*IIC–Increaseincostasapercentageofthetotalcropinvestment**DV–Dollarvalueoftheincreaseininvestmentcosts
Table14.–IncreaseinInvestmentCostswithRateIncreases(Coastal).
Investment Applied Water
$/AF Δ(50%) Δ(75%) Δ(100%) Δ(150%) Δ(200%)
($) (AF/acre) $210 $315 $368 $420 $525 $630
Vegetables $6,090 2.6 IIC 13.6% 18.0% 20.3% 22.5% 26.9% 31.4%
DV $0 $1098 $1234 $1369 $1640 $1912
Strawberries $27,583 2.4 IIC 2.7% 3.6% 4.1% 4.5% 5.4% 6.3%
DV $0 $1003 $1126 $1250 $1498 $1746
Raspberries $23,182 2.3 IIC 3.2% 4.3% 4.8% 5.3% 6.4% 7.5%
DV $0 $993 $1116 $1238 $1484 $1729
Blackberries $25,082 2.3 IIC 3.0% 4.0% 4.4% 4.9% 5.9% 6.9%
DV $0 $993 $1116 $1238 $1484 $1729
Nurseries $75,647 4.2 IIC 1.8% 2.4% 2.7% 2.9% 3.5% 4.1%
DV $0 $1785 $2006 $2226 $2667 $3108
*IIC–Increaseincostasapercentageofthetotalcropinvestment**DV–Dollarvalueoftheincreaseininvestmentcosts
‐32‐
8. CONCLUSION
For this report, a comprehensive project was launched that successfully estimated the
potentialwatersavingsinPajaroValley.Thisprojectconsistedof(1)aninterviewcampaign
withgrowers,(2)anETvalueconsultationwithexperts,and(3)astatisticalanalysisofdata
collected. Throughgrowers’ interviews,datawasacquiredregarding theamountofmoney
growers invest in crop production and their appliedwater data. ET datawas provided by
Michael Cahn of UC Davis and confirmed with similar data from Jean Caron of Laval
University.Thiswasasuccessfulproject,asitallowedustocalibrateourdatawithgrowers’
informationandcompareitwithexpertknowledge.
The potentialwater savings in Pajaro Valleywere estimated based on a combination of
results acquired from the field campaign, expert‐based criteria, remote sensing, andwater
metereddataanalysis.TheseresultssuggestthatPajaroValleycansave4,600to5,100AFof
waterperyearthroughconservationmeasures. Thesenumberswereattainedbyanalyzing
dataforthe2009wateryear,whichwasanormalyearconsideringprecipitationandclimate
conditions. A range of savings is proposed because there are some uncertaintieswith the
“UnknownAgriculture” category of crops. Most of the landuse datawas very specific, but
PVWMAwasunsureof16%ofthecropsgrowninthevalley. Ifwedonot includethe land
withunknownagricultureasanareawithpotentialwatersavings,thetotalwatersavingsof
the valley is estimated to be4,600AF/year. Ifwe consider the unknown agriculture and
assumethelandfollowsthesamedistributionofcropsastherestofthevalley,thenthetotal
potentialwatersavingsareestimatedas5,100AF/year.
This increase inwater savingswas shown to influence a direct decrease in revenue for
PVWMArangingfrom$862,000to$951,000peryear.Tocompensateforthislossinrevenue,
an increase in extraction fee rates was considered. This increase would affect farmers,
especially vegetable crop growers in the coastal zone. These growers currently receive an
estimated revenue of $3,910 per growing season (Monterey County Agricultural
Commissioner,2012). Ifwaterratesare increasedby50%($105/AF), theirrevenuewillbe
decreased 6.9% ($271) per growing season. This strategy will dramatically affect farmers,
lowering their net profit on crops. Strawberry, raspberry, blackberry and nursery growers
havealargerreturn,soincreasedwaterfeeswillaffectthemlessseverely.
‐33‐
It may be logical to suggest that all vegetable growers in Pajaro Valley should simply
switchtogrowingothercropstoavoidhighlosses.However,thisisnotassimpleasitsounds.
Thereisarotationofcropsbetweenstrawberriesandvegetables. Inessence,fieldsthatare
grownwithstrawberriesforagivengrowingseasonwillbegrownwithvegetablescropsthe
followingseason. Thisrotationispracticedinordertokeepthesoilproductivetomaintain
high strawberry crop yields. The other alternative is to fallow the land after the growing
season,butthatisnoteconomicallyfeasibleformanygrowers.
Fromthedatacollectedinthisreport,itisclearthatthereisroomforwaterconservation
in the Pajaro Valley. The PVWMA plans to complete seven projects, including a rigorous
conservationprogram.Thebeautyoftheprogramisthatitwillcontributetooveronethird
of theestimatedwatersavingspotential inthevalleywithout theconstructionofadditional
infrastructure.Instead,itseekstoimprovewatersavingsthroughtheinfrastructuregrowers
alreadyhave. Themainobstacle isclosingthegapbetweenourcurrentknowledgeandthe
traditionalbeliefsofgrowers.Withthedatacollectedfromthisproject,growerscanbebetter
informed about applyingwater based onET data. If all growers in the Pajaro Valleywere
briefedwith this information, the Pajaro Valley could very easily see yearly water savings
between4,600and5,100AF.
8.1. LIMITATIONS
In order to estimate the potentialwater savings in PajaroValley,we had tomake some
subjectiveassumptions.Theseassumptionsinclude(1)thecropsgrownunderthe“Unknown
Agriculture”categorycarrythesamedistributionastherestofthecropsinthevalley,(2)the
average ET value is reflective of the entire valley, and (3) all growers display the same
behavior as those interviewed in our sample area. For the first assumption, we cannot
accuratelypredictwhatisunknown.Secondly,ETchangeswithdifferentmicroclimatessoit
isunlikely thatoneETvalue is reflectiveof theentirevalley. Thecoastal regionsofPajaro
Valleyarefrequentedbyfogduringthenightandmorninghours,anditisextremelydifficult
togetanaccurateETvalueforareassubjectedtofoggyweather. GeographicallyspecificET
values could improve the water savings estimations. The third assumption is uncertain
becausewedidnotchoosetoincludeorganicgrowerswhousemorewaterthanconventional
growers. Thissuggeststhatnotallgrowersusedthesameamountofwaterasthose inour
‐34‐
sample. The potential water savings may have been overestimated by not accounting for
organiccrops.
Although there were some uncertainties that we tried to account for, this was a very
comprehensiveprojectthatyieldednumbersinwhichweareveryconfident.Manydifferent
data sourceswere compared in order to accurately estimate the potentialwater savings in
PajaroValley.
‐35‐
REFERENCES
Allen,R.,Pereira,L.,Raes,D.,andSmith,M.(1998).“Introductiontoevapotranspiration.”Crop
evapotranspiration – Guidelines for computing crop water requirements – FAO Irrigation anddrainagepaper56,FAO–FoodandAgricultureOrganizationoftheUnitedNations,Rome.
Bannister,M.,Palmisano,S.,Gutierrez,L.,Taylor,S.,(2012).“WatsonvilleAreaWaterRecycling
Project.”Brochure.PajaroValleyWaterManagementAgencyandCityofWatsonville.Watsonville,California.
Driscoll’s. (2013). “2013 Growing Regions and Loading Points.” 2013 Product Guide and
Availability Calendar. <http://www.driscolls.com/sites/default/files/2013PAC.pdf> (Apr. 7.2013).
Driscoll’s. (2013). “Where toBuy.”OurBerries. <http://www.driscolls.com/berries/where‐to‐
buy>(Apr.7,2013).Monterey County Agricultural Commissioner. (2012). “2012Monterey County Crop Report.”
Salinas,California.
Pajaro Valley Water Management Agency (PVWMA). (2012). “Membership Roster.” Ad HocBasin Management Plan Committee. <http://www.pvwma.dst.ca.us/board‐and‐committees/ad‐hoc‐bmp‐committee.php>(Apr.10,2013).
PajaroValleyWaterManagementAgency(PVWMA),2013,2012BasinManagementPlanUpdate,Draft:January2013,preparedbyCorolloEngineers,PajaroValleyWaterManagementAgency,Watsonville,CA,80p.,http://www.pvwma.dst.ca.us/about‐pvwma/assets/bmp_update_2012/2012_BMP_Update_Draft_Stamped_Jan2013_screen.pdf.
PajaroValleyWaterManagementAgency(PVWMA).(2013).“WaterRateIncrease‐2013.”
2013SpringNewsletter.<http://www.pvwma.dst.ca.us/media‐room/newsletters/2013_Spring_PVWMA_Newsletter_Final.pdf>(Sep.9,2013).
U.S. Geological Survey (USGS). (2013). “Distribution of Earth’s Water,” TheWorld’sWater,<http://ga.water.usgs.gov/edu/earthwherewater.html>(Apr.5,2013).
UnitedStatesCensusBureau. (2010). “Watsonville city,California.”2010DemographicProfile
Data. <http://www2.census.gov/census_2010/03‐Demographic_Profile_with_SF1geos/>. (Apr. 5,2013).
‐36‐
APPENDIX
ThissectionexplainsindetailtheproceduretocalculatethewatersavingsshowninFigure
A1‐1andA1‐2asfollows:
Column1(acres)wasprovidedbythePVWMA.
Column 2 represents the percentage of certain crops that are grown in the production
zonesofthetotalsurveyedarea.
Column3describestheirrigationmethodsgrowersused.
Column4istheAcreageFactorexplainedinsection5.1.2.
Column5(wateruse)istheaverageAppliedwaterestimatedinSection5.1.3.
Column6istheestimatedappliedwaterpercropandcolumn7representstheestimated
water savings. Calculations for these columns are explained in the following
section6.2.
Column8isthewateruseefficiency(WUE),basicallycomparingtheamountofwaterthat
canbesavedandtheamountofwaterthatisbeenused.Thiswasestimatedas
WUE=1–Wat.Savings(Column7)/AppliedWater(Column6).
Column9and10simplybreaksdownthepotentialwatersavingsintothedifferentcoastal
andinlandareas.Thereisalmostdoubletheamountofpotentialwatersavings
ininlandareasversusthecoastalareas.
TableA1‐1.–PotentialWaterSavings:LowerEnd.
‐37‐
TableA1‐2.–PotentialWaterSavings:UpperEnd.
There canbeapotential totalwater savings from4,600AFper yearup to5,100AFper
year.