Updated Source Water Assessment Seaside Water Department PWS #4100799 July 5, 2016 Prepared for: City of Seaside Prepared by: Department of Environmental Quality regon Agency Headquarters Wa ter Quality Program 81] SW Sixlh Avenue, Suite 600 Pm lland, OR 97204-1390 503-229-5696 (FAX) 503-229-6037 July 5, 2016 1TY711 Seaside Water Department Dale McDowell, Public Works Director 989 Broadway Seaside, Oregon 97138 Re: Updated Source Water Assessment for PWS # 4l00799 Dea r Director McDowell, On behalf of the Oregon Health Authority (OHA), the Oregon Department of Environmental Quality (DEQ) is pleased to provide your community with important information in this Updat ed Source Wat er Assessment. Th e updated assessment is intended to provide information and resources to assist you and your community to implement local drinking water protection efforts. Since the first sou rce water assessments were completed in 2005, state agencies have significantly expanded analytica l ca pabilities, including more detailed data for analyzing natural characteristics and potential pollutant sources. DEQ is currently completing the updated assessments for surface water systems and OHA is updating the groundwat er syst em assessments. As you know, assuring safe drinking water depends on public w ater suppliers implementing multiple successful practices. First, protect the drinking water source. Second, practice effective water treatment. Third, conduct regular monit oring for conta minants to assure safety. Fourth, protect the distribution system piping and finished wa ter storage from recontamination. Finally, practice competent water system operation, maintenance, and construction. These practices are collectively called "multiple barrier public health protection" . Source water protection is an important first step because starting with the best possible quality source water helps assure that water treatment can be effective at all t imes. Source water protection is accomplished by effective state public health programs, environmental protection, land use policies, pro-active land stewardship, and by implementation of local drinking water protection efforts by co mmunities and public water suppliers. The susceptibility of the public drinking wat er syst em source depends on both the natura l conditions in the wat ershed as well as t he ant hropogenic activities in the watershed. This letter, with attached figures and t echnica l information, constitutes your Updated Source Water Assessment. It supplements your original Source Wat er Assessment. One of the most important assets a public water syst em can have is accurate source water area mapping and visual resources to share with the community citizens and officia ls. The figures incl ude a new regional map view of your wat ershed, topographic basemap with the source area delineated, and maps with natural charact eristics, anthropoge nic land uses, potential sources of pollutants, and historic landslides. Information on anthropogenic land uses in a drinking wat er so urce area is important for evaluating potential pollutant sources and working with stakeholders upstream. Tables are provided that include a summary of the types of potential pollutant sources present in your drinking water source area. Th ere are also a variety of resources included in this document to assist you with drinking water source protection efforts. Appendix #1 provides a summary of how to use the information provided in the assessmeht to move forward to develop and implement source water protection. Appendix #3 lists websites and resources available to public water systems and community members seeking technical assistance for work on watershed protection. Appendix #4 provides brief descriptions and cont9ct information for grants and loans to fund bot h drinking water infrastructure and source protection projects. State agency resources are available to help you with mapping and information needs. Larger sizes of the source area maps and more details of landslide potentia l and other natural chara cteristics are available for you upon request (contact Steve Aalbers at 503-229-6798). DEQ is currently developing ''Resource Guides'' with more extensive information to assist public water systems in protecting their source waters. Resource Guides will be completed for both Oregon surface water systems and groundwater systems later this year. For direct assist ance and/or additional information regarding watershed prot ection, ca ll Sheree Stewart at DEQ (503-229-5413). For more information on drinking water policies and procedures, ca ll Casey Lyon at OHA (541-726-2587). Si ncerely, Sheree Stewart, Drinking Water Protection Coordinator Environmental Solutions Division Cc: Casey Lyon, Technical Services Manager, Oregon Health Authority Figure 1. Seaside Water Department (PWS 00799) Drinking Water Source Area and Adjacent Source Areas Gea rha rt PWS#4100062 Youngs River Lewis & Clark Water District ¤£101 North Fork/Barney Creek PWS#4100062 Youngs River Lewis & Clark Water District South Fork/Barney Creek 202 Sea side PWS#4100932 «¬ PWS#4100932 City of Warrenton City of Warrenton Lewis & Clark River Camp "C" Creek PWS#4100932 PWS#4100932 101 City of Warrenton ¤£ City of Warrenton Big South Fork - Little South Fork - Lewis & Clark River Lewis & Clark River ¤£26 ¤£101 PWS#4100799 Seaside Water Department Necanicum River ¤£26 Canno nBea c h PWS#4100799 Seaside Water Department South Fork Necanicum River PWS#4100164 City of Cannon Beach Elk Creek - West Fork PWS#4100802 Arch Cape Water District Shark Creek & Asbury Creek «¬53 PWS#4100505 Manzanita Water Department Middle Fork & West Anderson Creek PWS#4100554 1:180,000 City of Nehalem Miles 0 1 2 3 4 5 ® Bob's Creek Legend Sea sideWa Dept. ter Surfac eWa Intake ter Surfac eWa DW ter SAs Urba nGrowth Bound a ry CountyBound a ry Highways Sea sideWa Dept. ter .! op DrinkingWa Source ter (2010) Interstate surfac ewa intake ter Area City(ODOlimits 2013) T, U.S. Routes U.S. Thisda ana ta wa lysis co s nd uctedforstrategic planning purposes indrinking wa protec other ter tion.Ifuses O rego nRoutes aco re nsideredfortheda plea seta, co ntacDEQ’s t Drinking Wa Protec ter tionProgram fordetails on ho wthis querywa performedimportantis s undtoIt erstand . thelimitations and qualifica tionsof queries ensureto a ppropriateinterpretation ofdaNothis wa ta. rrantyexpressed impliedor mais d erega rdingtheac c urac yor utility. This disclaimer utility. applies bo indto th ividualuseof the da and ta aggrega use tewith other da ta. N oon te Base Layer: The hillsha d eco effec lor sho t wnhere of adtheis result d itionaproc l essing O rego nDeptof Environm entalQuality/Environm entalSolutions Division/Wa Quality ter Program o fdigital eleva tionmo d(DEM els 30meter - grid) da from ta 1:24000topographic ma A ps. DrinkingWa Protec ter tionProgram /GIS "hillsha d e”wa prod s ucedand first then coad lor justedThe . origina DEM l fileswere developed by P rojec tion:Orego nLam (Lam b ert Co b ert nformaConic) l theOR Dept.of Forestry.Add itionaproc l essingof the hillsha d eda with ta Red Green, , Blue GCS_No rth_America n_1983,Datum: D_N o rth_America n_1983 (RGB)co schem lor eresulted in the "orsha d e.sid"da tasetdisplayed here. The da set tais File:\\deqhq1\dwp\SWReports A Plan\Upda& SW te SW A providedforuse by theOrego nGeo spatialDa Center. ta 2016\!Tem plates\USW A_Fig1_SW Tem plateV icinityMa p.mxd P reparedby:jkh(21DEC2015, Rev. 29JUN Printed 2016(sda 05JUL2016 )), : (sda ) Figure 2. Seaside Water Department (PWS 00799) Drinking Water Source Area Erosion Potential (See Appendix 2 for Key to map details and metadata) po po V icinity Gearhart Legend Seaside po SeasideWaterDepartmen surface t waterintake SeasideDrinking WaterSource Area Cann onBeach Streams(NHD) with high erosion poten tial Lake(NHD) with high erosion poten tial Non otesImagery_ Mosaic2011base map: TheImagery Mosaic is from the 2011 N ationalAgriculture Imagery Stream(NHD) Servicemeter1 (NAIS), color aerial imagery from Farm Service Agen c y (FSA)/U.S. Dept.ofAgriculture (FSA)/U.S. (USDA). The imagery, collec tedduring thesum mandof er2009, 2005, can2011, be viewed down or loaded 1:100,000 fromOregon Imagery Explorer. 0 0.5 1 2 3 4 5 Miles µ O regonDepartmen ofEnvironm t enQuality/Environm tal enSolutions tal Division/Water Quality Program/ Thisproducinformational for is t purposes and may havenot been beprepared or suitable for, legal,for en gineeringor DrinkingWater Protec tionProgram/GIS surveyingpurposes. Users ofinformationthis should review and consult theprimary dataand information sources to ProjecOregon tion: Lamb (Lamb ert Conformal ert Conic), GCS_N orth_ American_ 1983 ascertainthe usability ofthe information. DEQ’s Drinking Water Protec tionProgram can provide information onhow DatumD_ : N orth_ American_ 1983 File:\\deqhq1\dwp\SW Reports APlan\Update& SW SW A thequeries were performed. isimportantun to It derstand the limitations and qualifications ofqueries en to sure 2016\!Tem plates\USW A_Fig2_SW Tem plateSen sitiveAreas_8x11.mxd appropriateinterpretation No ofwarrantythis data. expressed implied or madeis regarding the acc uracyutility. or PreparedAalbersby: S. (17MAY2016, Rev. 29JUN Printed: 2016), 05JUL2016 (sda) Thisdisclaimer applies individualboth to use theofanddata aggregate use with otherdata. Figure 3. Seaside Water Department (PWS 00799) Drinking Water Source Area Landslide Hazards Map (See Appendix 2 for Key to map details and metadata) DOGAMLa I ndslideInforma tion S ea side Legend op S ea sidesurface wa terintake S ea sideWaDrinking terSource L a ndslideDeposits (non-rock maincludes terial, ea rthand debris slides,flows, slumps, falls and complex)(DOGAM SL I IDO3.2) S caFla rp nks(DOGAM SL I IDO-3.2) op S ca(DOGAM rps SL I IDO-3.2) S trea m(NHD) Citylimits(ODOT, 2013) op Vicinity Gea rha rt S ea side CannonBea ch NotesDOGAMon LiDAR DEM I or Hillsha deba sela Digital yer: Eleva Model tion (DEM 10 meter)da tafrom Light Detection and Ra nging(LiDAR)) studies noLiDAR if daor, tais a vaila ble,US GS1:24000DEM da tawa sconverted tohillsha deby OR Dept. ofForestry (2008-12-23). The LiDAR(2008-12-23). da tasetava is ila bleat the website noted the in Key toFigures & 1:100,000 T a bles.