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

‐19‐

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 ‐‐‐

‐21‐

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.