Report: Identifying Public Lands Suitable for Urban Agriculture in the City of Federal Way, Washington
Nautilus Elementary School Community GardenPhoto credit: Federal Community Gardens FoundationWHERE TOGROWIdentifying PublicLands Suitable forUrban Agriculturein the City of Federal Way,Washington
2 | P a g eContentsEXECUTIVE SUMMARY................................................................................................................................ 3INTRODUCTION........................................................................................................................................... 4METHODOLOGY.......................................................................................................................................... 5RESULTS...................................................................................................................................................... 8DISCUSSION ................................................................................................................................................ 9NEXT STEPS............................................................................................................................................... 10APPENDICES.............................................................................................................................................. 11Appendix A. Data Dictionary................................................................................................................. 12Appendix B. Geospatial Analysis Methodology..................................................................................... 17Appendix C. Results Table..................................................................................................................... 25Appendix D. Sample Site Profiles .......................................................................................................... 27This report was prepared for Forterra and the City of Federal Way by Chris Hoffer andMatt Dressler. Spatial analysis was conducted by Matt Dressler and Christopher Walterusing ArcGIS 10 software provided by ESRI through the Nonprofit Organization Program.Special thanks to Kara Martin with Urban Foodlink and Kristen McIvor with the PierceConservation District, as well as staff from the City of Federal Way, for their thoughtfulcontributions in developing and conducting the inventory.Please contact Forterra with any questions about this report:901 5th Ave, Ste. 2200, Seattle, WA 98164; firstname.lastname@example.org; (206) 292-5907
3 | P a g eEXECUTIVE SUMMARYThis report describes the methodology and results of a spatial analysis to develop an inventoryof public land with the potential for urban agriculture in the City of Federal Way, Washington. Inpartnership with City staff, Forterra conducted the analysis over several months in 2012 and2013. The objective was to assess all public lands relative to a suite of characteristics thataddress their potential suitability for several forms of urban agriculture. All input and resultdatasets were delivered to the City in an ArcGIS geodatabase. In addition, City staff wasprovided KML versions of key datasets so that they would be able to directly access and interactwith the results using Google Earth.Using geographic information system (GIS) technology and publicly available data, Forterraevaluated potential sites based on suitability criteria relevant to urban agriculture. These criteriafell into several general categories: land ownership and management; land cover characteristicsand growing area; land use characteristics; topography; soil suitability; transportation access;and neighborhood demographics.In all, the assessment identified 362 candidate sites with a combined total of 256 acres of landpotentially suitable for urban agriculture. Among the candidate sites, 192 met the criteria forpotential cultivation: 26 met the minimum area requirements for small community gardens,another 76 (totaling 20.5 acres) for large community gardens or food forests, and another 90(totaling 233 acres) for urban farms. In addition, 490 acres were identified as having thepotential for agroforestry activities.This analysis represents the first step in identifying new sites on public lands suitable for urbanagriculture. With this information, the City of Federal Way now moves to the next phase ofreviewing the results, engaging the community, gathering additional information and planningadditional urban agriculture projects for the benefit of residents."Almost any barrier [to urban agriculture] can be overcome byan excited community group."Kristin MclvorCommunity Garden CoordinatorPierce County Conservation District
4 | P a g eINTRODUCTIONHealthy living in Federal WayIn 2011, the City of Federal Way was awarded a Healthy Eating Active Living grant from SeattleKing County Public Health through the Communities Putting Prevention to Work programfunded by the Centers for Disease Control and Prevention. This work involved conducting afood landscape assessment1 to gain a better understanding of the community’s access to food,by mapping and analyzing the retail environment, land use patterns, demographics, and streetnetwork.The results of this assessment demonstratedthe need for new policies and projects topromote access to food and healthy living inFederal Way. Key findings from the reportdemonstrate that not only does Federal Wayhave a high rate of adult obesity, but also thatmost residents live closer to fast foodrestaurants and convenience stores than tohealthy food sources like supermarkets.Urban agricultureAs revealed by Federal Way’s food landscape assessment, many residents have limited accessto fresh produce and healthy foods. One strategy identified by the City to ensure that residentshave better access to healthy food is to increase access through urban agriculture.Urban agriculture is an umbrella term encompassing a wide range of activities involving theraising, cultivation, processing, marketing and distribution of food in an urban environment.Urban agriculture includes a wide spectrum of activities such as home gardens, communitygardens, urban farms, cottage food operations, farm stands, and farmers marketsThere are many reasons for municipalities to encourage urban agriculture. In addition toimproving health and nutrition by increasing access to healthy food, urban agriculture providesenvironmental benefits, such as improving air and water quality, and helps to preservecultivatable lands. It also offers social benefits to the community such as capacity building andcreating an enhanced sense of place. Community gardens reduce family budgets, facilitateneighborhood and community development and create opportunities for recreation, exerciseand education.To help promote urban agriculture, the City of Federal Way received technical assistance in2012 from Forterra, as part of the Environmental Protection Agency’s Building Blocks forSustainable Communities program. This technical assistance included engaging the communityin conversations about urban agriculture, amending current policies and regulatory codes, anddeveloping a land assessment protocol for identifying public lands that could be used forcommunity gardens and other forms of urban agriculture.1Kara E. Martin, Urban Food Link with Branden Born and Eva Ringstrom, Northwest Center for Livable Communitiesand Amalia Leighton, SvR Designhttp://www.urbanfoodlink.com/wp/wp-content/uploads/2011/11/FederalWayFoodLandscape.pdfFood landscape assessment key findings Federal Way has the county’s thirdhighest adult obesity rate. Over 87% of the city’s land base is morethan one half mile from a super market. There are nearly four times as many fastfood restaurants and convenience storesas there are supermarkets, small grocerystores and produce vendors, combined.
5 | P a g eLand inventories for urban agricultureMunicipalities throughout the country have conducted inventories of publicly owned land thatmay be suitable for urban agriculture. These inventories have allowed cities and residents toidentify the most promising lands for community gardens and other types of urban agriculture,as well as to calculate potential food productivity. Other examples in the Northwest includeSeattle and King County, as well as Portland, Oregon and Vancouver, British Columbia.In her review of recent inventories inmunicipalities across the country2, Megan Horstdeveloped a general framework for conductingan urban agriculture land inventory. Expandingon this framework, Forterra worked with the Cityto develop a methodology and then to conduct apublic land inventory. The purpose of this projectwas to provide an initial inventory of publiclyowned lands and to identify their suitability forurban agriculture. This built on the City’s existingwork to assess its food landscape and to adoptpolicies in support of urban agriculture. Theinventory is intended to provide residents,nonprofits, and City staff with information that can support an increase in urban agriculture andfood production. Looking ahead, the inventory has the potential to help both residents and Cityplanners identify and consider specific locations for different types of urban agriculture.METHODOLOGYUsing the tools and analysis techniques available in geographic information systems (GIS),Forterra conducted an inventory of publicly owned land in Federal Way and evaluated thesuitability of that land for urban agriculture based on a set of criteria. This process was informedby reviewing methodologies and best practices of other land inventories conducted across thecountry, with a focus on local efforts in Seattle, Portland, and Vancouver, BC.After meeting with planning and GIS staff at the City of Federal Way, we created and prioritizeda list of suitability criteria. These criteria fit under several general categories of suitability forurban agriculture: land ownership and management; land cover characteristics and growingarea; land use characteristics; topography; and soil suitability. Additionally, we included criteriathat extended beyond the characteristics of the site itself, such as transportation access anddemographics of the surrounding area. This additional information can be used to prioritizepotential sites based on how likely they are to benefit residents with the least amount of accessto healthy food and other benefits of urban agriculture.Data were acquired from the City of Federal Way as well as a variety of local and federalsources including King County, imagery from the US Department of Agriculture, LIDAR datafrom the Puget Sound Lidar Consortium and 2010 US Census information. Based on factors2“A Review of Suitable Urban Agriculture Land Inventories.” Megan Horst, February 10, 2011.http://www.planning.org/resources/ontheradar/food/pdf/horstpaper.pdfConducting a land inventory1) Determine objectives2) Involve stakeholders3) Conduct inventorya. Establish an initial set ofavailable landsb. Establish suitability criteriac. Assign scoresd. Present results4) Plan next steps
6 | P a g eMinimum criteria for cultivation At least 2,500 square feet Not in a sensitive area or buffer Not forested* Average slope less than 10%Potential cultivation category Small community garden (2,500 – 5,000 ft2) Community garden (2,500 ft2– 0.5 acres) Urban farm ( > 0.5 acres)* Forested sites meeting other minimum criteria wereclassified as potentially suitable for agroforestry.such as the timeframe for conducting the inventory, the availability of necessary data and initialpriorities, not all potentially useful information was collected. The Appendices of this reportinclude both a data dictionary and detailed description of the methodology used for geospatialanalysis.For land ownership, we catalogued the name and type of the agency with jurisdiction andmanagement of each property, recognizing that public properties could be owned by city,county, state, federal government or other local entities. We included both the owner of theproperty, such as the City of Federal Way, as well as the managing agency, such as the ParksDepartment. Given that the City was in the process of updating its policies and codes as theyrelate to urban agriculture, we also catalogued land use compatibility such as zoning andcurrent use.To determine the potentially cultivatablearea of each site, we calculated the amountof land available after excluding areas thatwere deemed unsuitable for growing food.Unsuitable areas included: impervioussurfaces (such as buildings, pavement, andsidewalks); forested areas covered by treecanopy; sensitive areas and theirassociated buffers (wetlands, rivers andlakes), and areas with slopes greater than10%. Based on this information, sites werefurther categorized by the size ofcultivatable area, indicating likelyappropriateness for small communitygardens, large urban farms, etc.Importantly, no site was excluded from the inventory even if it was determined to be unsuitablefor cultivation. Although immediately cultivatable sites were of the most interest to the City, itwas agreed that many sites could be used for other forms of urban agriculture. Paved areascould support container gardening or farmers markets, for example, while forested sites couldsupport agroforestry, and sites with extreme slopes might still be developed through terracing.Soil suitability was also important to catalog, both by looking at the USDA farm soil rating aswell as potential arsenic contamination. Although arsenic occurs naturally in the environmentand is not typically of concern for urban agriculture, a copper smelting plant that operatednearby until 1986 left significantly elevated levels of arsenic in surrounding soils, including muchof Federal Way. For each site, the area and concentration of detected arsenic contaminationwas reported in parts per million based on data from the Washington State Department ofEcology. Those sites with arsenic levels above 20 ppm (the state cleanup level) may still besuitable for cultivation by bringing in new soil, or for other forms of urban agriculture such ascontainer gardening or farmers markets.Given the unique role for urban agriculture to improve equitable food access, the City was alsointerested in surrounding demographic characteristics of each site. This included identifyingareas with higher levels of poverty (with respect to both federal standards and in comparison tothe rest of the City). Additionally, the inventory includes the percentage of residents near each
7 | P a g esite who are people of color, as these individuals are disproportionately impacted by a lack ofaccess to healthy food.Population density was also measured, recognizing that more dense and urban neighborhoodsstand to benefit the most from urban agriculture opportunities, given that less developed areasare likely to have greater access to land for cultivation. Transportation accessibility was alsoanalyzed. This included the proximity of the site to bus service as well as a site’s activetransportation potential. This information can be helpful in determining which sites are mostaccessible for transit-dependent residents.Summary of land suitability categories and criteriaSUITABILITY CATEGORY AND RATIONALE SUITABILITY CRITERIAOwnership and ManagementTo identify jurisdiction Ownership Jurisdiction Managing Agency or DepartmentLand Cover Characteristics and Growing AreaTo determine suitability for cultivation andtype of urban agriculture Impervious Area Forested Area Sensitive Area Steep Slope Area Potentially Cultivatable Area Potentially Cultivatable Suitabilityby Type Potential Agroforestry AreaLand Use CharacteristicsTo determine compatibility with current andpotential use Current zoning designation Current land useTopographyTo determine ease of developing site for urbanagriculture SlopeTransportation AccessibilityTo determine site access by transit-dependentresidents Proximity to bus service Active Transportation PotentialRatingSite Soil SuitabilityTo identify soil quality and potential for arseniccontamination Potential Arsenic Pollution USDA Farm Soil RatingEquityTo determine proximity to communities withmost benefit from, and least access to, urbanagriculture Food Equity Residential Density EthnicityOther Characteristics Property Size Site Name
8 | P a g eRESULTSUsing Geographic Information Systems and data from the City of Federal Way, King County,and Federal agencies, 362 candidate sites were identified as public land potentially suitable forurban agriculture. Detailed results are included in the appendices, as are sample site profilesthat illustrate how the inventory can be used to determine suitability for different types of urbanagriculture.Among the candidate sites, 192 sites covering 256 acres met the criteria for potential cultivation,meaning that the site included at least 2,500 square feet that was not forested or impervious,not in a sensitive environmental area, and not steeply sloped. Among these sites, 26 were mostappropriately sized for small community gardens, 76 sites (totaling 20.5 acres) for communitygardens or food forests, and 90 sites (totaling 233 acres) for larger urban farms. An additional490 acres among 208 candidate sites were forested, with the potential for agroforestry. In thiscontext, food forests refer to the cultivation of edible trees and shrubs, while agroforestry refersto the cultivation of forest products alone or in combination with agriculture.Among the 192 sites with potentially cultivatable land: 143 are within a ¼ mile of a bus stop More than 180 have a medium or high Active Transportation Potential score 161 have soils with a USDA farm soil rating of “statewide importance” or better 32 sites are within census tracts where 40% or more of the tract is living at 200% of thefederal poverty level 43 sites are within census tracts with a median household income at or below $45,207,which is 80% of Federal Way’s median household income 104 are owned by the City of Federal Way, 31 are owned by the Federal Way SchoolDistrict, and 22 are owned by the Lakehaven Utility District 21 are public school properties, 16 are open space and 17 are vacantSummary of key characteristics of potentially cultivatable sitesCATEGORY RESULTSOwnership and Management More than half are owned by the City 100 acres are owned by the School DistrictTransportation Accessibility 75% are within a ¼ mile of a bus stopSite Soil Suitability 51% have very low levels of arsenic contaminationEquity About 22% are in neighborhoods at or below 80% ofFederal Way median household income 3 out of 4 sites are in neighborhoods where 25% - 50%of residents are people of color
9 | P a g eDISCUSSIONThe reality of GIS analysis, like any modeling process, is the unavoidability of a certain amountof error. The goal is to conduct analyses with the highest level of accuracy and precisionpossible given inherent limitations in data, methods and resources available. The following is adiscussion of some known limitations in this analysis.The first source of limitations in this analysis is related to data. For example, the arsenicconcentration and farming soil datasets are both subject to sampling error and limitationsrelated to the mathematical interpolation involved with their creation. The U.S. Census dataused in the analysis are three years out of date and potential inconsistencies in the record ofownership, management purpose, site name and use will have led to inaccuracies in theaggregation of adjacent parcels as single properties. Also, while the tree canopy dataset wasdetermined to be 92% accurate overall, it will underestimate the canopy in some locations andoverestimate it in others, corresponding to an overestimate or underestimate, respectively, ofthe amount of potentially cultivatable area for different sites.The analysis methodology makes a number of simplifications. The proximity of each candidatesite to the nearest bus stop is calculated as Euclidean (straight line) distance rather than thetrue route taken using the existing transportation network. In addition, all areas with slopes ofgreater than 10% are predicted to be unsuitable for cultivation, which may not always be thecase. Regulatory buffers around sensitive areas such as creeks and wetlands may in somecases be suitable for cultivation and these areas will be missed in this analysis. The actualextent of land suitable for agroforestry will in some cases be smaller than the results suggest asthe analysis does not consider the important factor of canopy density. Finally, the three Equitycharacteristics (Food Equity, Residential Density and Ethnicity) reported for each site are basedon a spatial average of Census demographics reported for the surrounding neighborhood. Whilethis is a commonly used analysis technique - in fact, the only feasible method - it produces trulyaccurate results only where household income levels, racial makeup and household density areevenly distributed throughout the surrounding area: conditions that are rarely, if ever, present inthe real world.Nevertheless, despite the existence of some error, this analysis should prove very useful innarrowing the range of potential candidate sites. We recommend that inventory be used moreas a tool to identify sites for further consideration than to make exclusionary decisions or takeaction based on the analysis alone. Reviewing the data using Google Earth will allow city staffto take a first step in this direction by “virtually” ground truthing the results.
10 | P a g eNEXT STEPSThis land inventory represents the first step in identifying the suitability of public lands for urbanagriculture. There are many additional opportunities to share the results of the inventory andengage the community, as well as to gather additional information and explore the suitability ofother types of land for related uses. The following are potential next steps for the City toconsider:1. Share results and engage the community.Inventories conducted in other communities have relied on stakeholder input to ensure theinventory is comprehensive. Portland, for example, established a Technical AdvisoryCommittee consisting of city staff and members of a citizen-based Food Policy Council.Focus groups and input from additional stakeholders, such as community garden leadersand nonprofits, were also important in establishing land criteria and reviewing preliminaryresults. Using this inventory as a starting point, there is significant opportunity to engage thecommunity in refinement and utilization.2. Gather additional information.Inventories are typically iterative, so there is opportunity to gather additional information andrefine the inventory. For example, other inventories have catalogued parking and sidewalkaccess to sites, as well as proximity to existing community gardens, access to waterinfrastructure, and the amount of shade or solar access for a given site. There is alsoopportunity to “ground truth” potential sites; while this can be accomplished through actualsite visits, many inventories with large numbers of sites have successfully used satelliteimagery and tools such as Google Street View to save time.3. Rank, classify and prioritize potential sites.Engaging the community and gathering additional information will allow the City andresidents to further rank, classify, and prioritize sites. For example, medium to large sites forcommunity gardens or urban farms may be a high priority, as well as those sites inneighborhoods with higher levels of poverty and lower access to healthy food. Sites withwater infrastructure and parking access, or those managed by particular agencies ordepartments, may also be the most feasible to develop for urban agriculture.4. Create an online interactive site locator to assist public in identifying and accessingpotential urban agriculture sitesIn addition to training City staff on how to share information from the inventory with thepublic, many communities have also turned the inventory into a publicly available,interactive, online land locator. This empowers residents and nonprofits to identify andconveniently explore potentially suitable lands for urban agriculture.5. Conduct additional assessment.This inventory is focused on the suitability of publicly owned land for urban agriculture, butthere could be other uses to consider, such as suitability for urban livestock, agro-forestry, orcommunity orchards. Additionally, privately-owned land may also worth identifying;churches, for example, are regularly involved in community gardens. Other assessmentsmight focus on parking strips or even the food potential from private home production.
11 | P a g eAPPENDICESAppendix A. Data DictionaryAppendix B. Analysis MethodologyAppendix C. Results TableAppendix D. Site Profiles
Appendix A. Data DictionaryFeature Class:FederalWay_PublicLands_UrbanAgSuitabilitySuitability CriteriaReportingCategoriesField Name Field Alias Field DescriptionLand Cover Characteristics and Growing AreaImpervious Areaunsuitable forcultivation< 2500 sq. ft.;2500-5000 sq. ft.;5000-21780 sq.ft.; > 21780 sq. ft.IMPR_SF IMPERVIOUS_SURFACE_SQFTTotal area (sqft.) of site that is animpervious surface as representedby building footprints, pavementand sidewalksSteep Slope Arealikely unsuitable forcultivationArea SLOPE_10 STEEP_SLOPE_SQFT Total area (sqft.) of site with aslope greater than 10%Percent SLOPE_10PCT STEEP_SLOPE_PCT Percent of site with a slope greaterthan 10%Sensitive Areapotentially suitable forcultivation< 2500 sq. ft.;2500-5000 sq. ft.;5000-21780 sq.ft.; > 21780 sq. ft.SEN_AREA SENSITVE_AREA Total area (sqft.) of a site that iscovered by lakes, wetlands andwater courses and their associatedbuffersForested Areapotentially suitable forcultivationArea FOR_SQFT FORESTED_SQFT Total area (sqft.) of a site thatcovered by mature tree canopy.Percent FOR_PCT FORESTED_PCT Percent of a site covered by maturetree canopyPotentially CultivatableArealikely suitable forcultivationArea POTEN_CUL_SF POTENTIAL_CULTIVATION_SQFTTotal area (sqft.) of a site that ismost suitable for cultivation in thatit does not include any of thecategories above (forest, sensitve,impervious or steep slopes)
13 | P a g eArea POTEN_CUL_ACRESPOTENTIAL_CULTIVATION_ACRESTotal area (acres) of a site that ismost suitable for cultivation in thatit does not include any of thecategories above (forest, sensitve,impervious or steep slopes)unsuitable; smallcommunitygarden;communitygarden, foodforest; urbanfarm, food forestPOTEN_CUL_SUIT POTENTIAL_CULTIVATION_SUITABILITYSuitable category of urbanagriculture based on minimumcultivatable area requirements forthat category: unsuitable (< 2,500sqft.); small community gardens(2,500-5,000 sqft.); communitygardens and food forests (5,000-21,780 sqft.); urban farms and foodforests (> 21,780 sqft.). Note thatsites that qualify for categorieswith larger size requirements alsoqualify for those with smallerrequirements.Area FOR_FOOD FORESTED_FOOD Total area (sqft.) of a site that ismost suitable for cultivation butthat is covered by tree canopy(does not include sensitive,impervious or steep slopes).Potentially suitable for agroforestryor food forest cultivation.Ownership and ManagementOwnership Jurisdiction Name OWN_1 OWNERSHIP Name of government entity thatowns siteFederal, State,County, CityOWN_TYPE OWNERSHIP_TYPE Hierarchical level of governmentthat owns site
14 | P a g eManaging Agency orDepartmentName orabbreviationOWN_DEPT OWNERSHIP_DEPT Name of agency or departmentthat manages site (e.g. DOT, Parks,Public Works)Land Use CharacteristicsZoning (site only) Current zoningdesignationCUR_ZONE CURRENT_ZONE City of Federal Way zoningdesignation code(s)Use Category (site only) Land use category USE_CAT USE_CITY Existing primary land use accordingto City of Federal WayLand use category USE_PRESENT USE_COUNTY Existing primary land use accordingto King County AssessorTopographySlope 0-5%; 5-10%;>10%SLOPE_AVG SLOPE_AVG Average grade across entire sitecategorized according to suitabilityfor urban agriculture (0-5% good; 5-10% acceptable; >10% unsuitable)Transportation AccessibilityProximity to Bus Service <0.25 mi; 0.25-0.5 mi; >0.5 miPROX_BUS PROXIMITY_BUS Straight line distance (miles) fromsite to nearest bus stop
15 | P a g eActive TransportationPotential RatingInteger ATP_SCORE ATP_SCORE Numerical Score from 4-29 (low-high) representing ActiveTransportion Potential Rating forsite. Rating based on locationrelative to city transportionnetwork as determined in studyconducted for the city of FederalWay.Site Soil SuitabilityPotential ArsenicPollutionNon-Detect to20.0 ppm; 20.1ppm to 40.0 ppm;40.1 ppm to 100.0ppm; 100.1 ppmto 200.0 ppmARSC_CONCEN ARSENIC_CONCENTRATIONDetected arsenic soil concentrationrange(s) (ppm) present in soilswithin site boundaryUSDA Farm Soil Rating Area SOIL_PRIME SOILS_PRIME_FARMLAND Area (sqft.) of site containing soilsdesignated Prime Farmland(excellent for agriculture) by USDAsoil surveyArea SOIL_SWI SOILS_STATEWIDE_IMPORTANCEArea (sqft.) of site containing soilsdesignated Statewide Importance(good or acceptable for agriculture)by USDA soil surveyArea SOIL_NOTPRIME SOILS_NOT_PRIME Area (sqft.) of site containing soilsdesignated as poor for agricultureby USDA soil survey
16 | P a g eEquity IssuesFood Equity Yes, No EQUITY_POV200 EQUITY_POVERTY Whether or not site is located in aCensus Tract for which 40% or moreof 2010 population is living at orbelow 200% of Federal PovertyLevel.Yes, No EQUITY_MHHIN80 EQUITY_MEDINCOME Whether or not site is located in aCensus Tract for which 2010 medianhousehold income is at or below80% of Federal Ways medianhousehold incomeResidential Density <1:1; 1:1-4:1;4:1-8:1; >8:1HH_DEN HOUSING_UNITS_ACRE Average density in 2010 of housingunits per acre for all Census blockswithin a quarter mile of siteEthnicity 0-25% minority;25-50% minority;50-75% minority;>75% minorityETH_PCTMN ETHNICITY_PCTMINOR Average percent minoritypopulation in 2010 for all Censusblocks within a quarter mile of siteOther CharacteristicsProperty Size Area AREA_SF AREA_SQFT The area (sqft.) of site ascalculated by GISArea AREA_ACRES AREA_ACRES The area (acres) of site ascalcuated by GISIdentification Integer SITE_ID SITE_ID Unique numeric ID for each siteName FACILITY_NAME FACILITY_NAME Site name according to City ofFederal Way
17 | P a g eAppendix B. Geospatial Analysis MethodologyGoal Conduct an inventory of all public lands within the city of Federal Way to assess their suitability for UrbanAgriculture--specifically community gardens, urban farms and food forestsScope & Deliverables Identify and assess candidate sites for their suitability based on all criteria identified in project scope.Deliver results dataset in ArcGIS file geodatabase 9.3 format. Include all datasets utilized in analysis, asummary of the suitability criteria and a description of the analysis methodology .Spatial Reference GCS North American 1983 HARNNAD 83 HARN State Plane WA North FIPS 4601 FeetProjection: Lambert Conformal ConicSoftware ArcGIS 10; XtoolsPro; Microsoft Word/ExcelInputs From City of Federal Way GIS Department: geodatabase dated 20120803: Federal Way Property, Federal WaySchool District Property, Lakehaven Utility District Property, Washington State Propety, FW_imperv,FW_climits, FW_open_space, FW_parcels, FW_parks, FW_publicparcels, FW_special_district_prop,FW_landuse, FW_lakes, FW_puget, FW_Soils, FW_wetlands, FW_streams, FW_ATPfin_201121,Tacoma_SmelterPlume, 201004, FW_ortho_6inch_2007, FederalWay_ActiveTransportaionStudy_gdb dated2011.From Other Sources: King_blk2010_pophu, King_blk2010_sf1po3, KingCounty_BusStop_2012,SOILS_King_SSURGO, KingLidar_DGM_6ft_2003, NAIP 2009 with near infrared band, acs_s053b19013 (2010Tracts joined to ACS table: median household income in past 12 months in 2010 inflation adjusted dollars) andesj_acs_area_poverty200percent (percentage of people living at 200 percent of the Federal Poverty Level inKing County by census tract) from American Community Survey/2010 U.S. Census via King County
18 | P a g eAction Feature Class Name Data Sources, Dates Spatial Analysis Technique NotesCreate analysis file gdband three featuredatasets--Inputs,Intermediates, Results;Include both input andderived raster datasetsFederalWay_UrbanAg_LandInventory.gdbSee List Below import datasets required for analysis Ensure singlegeographiccoordinate systemand projection for alldatasets utilized inanalysisCreate Candidate SitesFeature ClassSites_UrAgCandidatesFW Land PublicParcels, 20120803; FWLand Special DistrictProperty (includingLakehaven Utilityproperties) 20120803Remove overlap in datasets, merge(adjacent) parcels/polygons with sameownership to create a "property" leveldataset.Delete extraneousfields and dissolve onessential attributes,run single tomultipart, create andpopulate attributefields described insuitability criteriamatrix for whichdata already existsvia joins to otherFW_DBO featureclasses dated August,2012. Create uniquesite ID for eachproperty.Identify USDA farm soilattributes (type andamount) for each siteSoils_SitesSoils SOILS_King_SSURGO,20080605 (subset ofU.S. Dept. ofAgriculture, NaturalResources ConservationService data)Intersect candidate sites with soil data.Dissolve on Site ID, sum areas by site foreach soil category and report areas in SQFT.Create field for each soil type in resultsdataset and populate via join.RedefinedCoordinate System(Project Tool) andsoil dataset did notline up with citylimits along SEboundary. approx 10sites along SWboundary haveportions of siteoutside soilintersection;
19 | P a g eAction Feature Class Name Data Sources, Dates Spatial Analysis Technique Notescalculated soil typesand area for theseregions assumingcontinuity ofadjacent NRCS soildata and editedintermediate datasetbefore joining toresults.Identify presence andconcentration of arsenicin candidate site soilsSoils_ArsenicContaminationTacoma_SmelterPlume, 201004; WA Dept. ofEcologyIntersect candidate sites with smelterplume data. Dissolve on Site ID, reportconcentrations in ppm and concatenatecategories where multiple exist within asite. Join to results.RedefinedCoordinate System(Project Tool) andreported arsenic soilconcentration in ppmas all of Federal Wayis within the ASARCOsmelter plume.Identify sensitive areas,water features andother regulatory bufferareas likely unsuitablefor any form of urbanagricultureLandcover_SitesSensitiveAreaFW_Streams,FW_Wetlands,FW_Lakes, 20120803.Buffer streams 50 feet, buffer wetlandswith associated buffers identified inFW_Wetlands. Exclude culverts fromstream dataset. Merge all above with lakes,dissolve to remove any overlap, andintersect with candidate sites. Dissolveagain on site ID and report areas in fourcategories, <2500 sq ft, 2500-5000 sq ft,5000-21780 sq ft, > 21780 sq ft.Definition ofsensitive areas forpurposes of analysisper conversationwith Erik Earle.
20 | P a g eAction Feature Class Name Data Sources, Dates Spatial Analysis Technique NotesIdentify impervioussurfaceLandcover_SitesImperviousFW_Built_DBO_imperv,20120803.Intersect candidate sites with imperviousdata. Dissolve on Site ID, SUM area fieldand join to results.Impervious dataincludes buildingfootprints,pavement,sidewalks, pavementedge. Area reportedin four categories;<2500 sqft, 2500-5000 sq ft, 5000-21780 sq ft, > 21780sq ft.Calculate distance tonearest bus stopEquity_PovertyMedianIncomeKingCounty_BusStop_2012Calculate Euclidian distance (straight line)from candidate site polygons to nearest busstop with Near Tool. Report distance inthree categories; <0.25 mi; 0.25-0.5 mi;>0.5 mi.Calculate average activetransportation potentialvalue for each siteTransportation_SitesATPFW_ATPfin_201121 Convert atp raster pixel type from floatingpoint to integer with Integer tool, convertraster to polygon, intersect with candidatesites, run zonal statistics to derive meanvalue for each site.Calculate Average Slope Table: FW_SitesSlope_ZonalStatsKing_DGM6ft_2003(Lidar)Create slope raster, mask by city limits, runInteger tool on raster (round all values downto integers), then zonal statistics for eachsite to identify mean value for each site.Create new field and report average slopein categories of 0-5%, 5-10%, > 10%;Identify Steep Slopeslikely unsuitable forurban agricultureLandcover_SitesSlope10 King_DGM6ft_2003(Lidar)Reclassify slope raster (0-10%, 10-20%,etc.), convert to polygon, create newfeature class with slopes 10% and greater,intersect with sites, report area in sq. ftand percent of site.
21 | P a g eAction Feature Class Name Data Sources, Dates Spatial Analysis Technique NotesCalculate a weightedaverage of housing unitsper acre and percentminority population forall Census Blocks within1/4 mile of eachcandidate site.Equity_EthnicityDensity;Equity_EthnicityDensity_Calculations2010 U.S. Census Blocklevel dataCreate subset of Census Block data thatintersects city limits polygon, add fields andcalculate area of census blocks in acres,number of households per acre, totalminority population and percent minoritypopulation. Buffer candidate sites 1/4mile, add field and calculate buffer area inacres, then intersect with census blockdata. Add fields and calculate area ofintersect polygons in acres, and percentarea of buffered polygons. Add field andmultiply percent area of buffered polygonby census block HH density to derive arelative HH density for each intersectpolygon. Add field and multiply percentarea buffered polygon by percent minoritypopulation to derive a relative percentminority population for each intersectpolygon. Dissolve on site ID and SUM thetwo relative percent fields described above.Add two text fields and reportweighted/spatial HH density and percentminority populations in categories definedin suitability matrix. Join back to resultsdataset and use the field calculator totransfer these weighted average values foreach site.
22 | P a g eAction Feature Class Name Data Sources, Dates Spatial Analysis Technique NotesIdentify high-needpopulations in FWrelated to FederalPoverty Level andMedian HouseholdIncome: Food EquityindicatorsEquity_PovertyMedianIncome2006-2010 AmericanCommunity Survey,U.S. Census Bureau;2010 U.S Census TractData augmented byKing CountyIdentify census tracts meeting criteria of"high need populations" defined as 40% orhigher of census tract is living at 200%Federal Poverty Level. Intersect candidatesites (by centroid) with census tracts andidentify candidate sites with centroids intracts meeting criteria (yes, no). Thenidentify census tracts meeting criteria of"high need populations" defined as medianhousehold income of census tract is at orbelow 80% of Federal Ways median income(FW median income in 2009, $56,509 ; 80%is $45,207). Median Income from 2006-2010, same period as Census Data.Intersect candidate sites (by centroid) asabove and attribute as meeting secondcriteria (yes, no).Percent ofPopulation withinCensus Tract living at200% Federal PovertyLevel and MedianHousehold Income byCensus Tract basedon estimates from2006-2010 AmericanCommunity Survey,U.S. Census Bureau.
23 | P a g eAction Feature Class Name Data Sources, Dates Spatial Analysis Technique NotesDetermine the area andpercent of site coveredby tree canopyLandcover_SitesCanopy;Landcover_TreeCanopyNational AgriculturalImagery Program(NAIP), 1 meterresolution, 4 BandImagery, 2009.An image analysis and classification was runon the NAIP imagery using the NDVI tool andthen the ISO Unsupervised Classificationtool. Steps included extracting by mask asubset of the imagery, running the NDVIanalysis, then running the isocluster toolcreating 50 classes and assigning values tothe pixels (canopy, bare soil, other), thenreclassifying the raster and converting topolygon. Features < 100 sq. ft. weredeleted and remaining polygons intersectedwith the candidate sites. To improve thequality of the canopy dataset, the polygonswere buffered 10 feet in all directions,converted to lines, buffered another 10feet, and then erasing these buffered linepolygons from the buffered tree canopy.This technique "reclaimed" area of actualtree canopy that was missed in theclassification--i.e shadows in areas ofcontiguous tree canopy--and returned thecanopy data to its original outer dimension.The 4-band NAIPImagery wasacquired from UnitedStates Department ofAgriculture for asmall fee, given theappropriate spatialreference andmosaicked togetherfrom 4 quadscovering FederalWay. Also, anaccuracy assessmentof the final site/treecanopy dataset wasconducted bygenerating 50random points andchecking for dataaccuracy at eachlocation. Theassessment found thetree canopyclassification to be92% accurate.
24 | P a g eAction Feature Class Name Data Sources, Dates Spatial Analysis Technique NotesDetermine areapotentially suitable forcultivationLandcover_SitesPotentialCultivatable;Landcover_SitesNonCultivatableLandcover_SitesCanopy, 2009;Landcover_SitesSlope10, 2003;Landcover_SitesSensitiveArea,2012; Landcover_SitesImpervious, 2012The four "unsuitable for cultivation"datasets (SitesCanopy, SitesSlope10,SitesSensitiveArea, SitesImpervious) weremerged together and then dissolved toremove overlap. An intersection with thecandidate site polygons was run yielding theLandcover_SitesNonCultivatable featureclass. This dataset was erased from thecandidate site polygons. What remained inthe candidate was further refined byremoving polygons that overlaid athleticfields, water, beaches and obvious shadowsas these areas were considereduncultivatable. The remaining area becamethe Landcover_SitesPotentialCultivatablefeature class. An intersection was run withthe candidate sites and the results reportedin four categories related to various formsof urban agriculture: < 2500 sq. ft.unsuitable; 2500-5000 sq. ft. marginallysuitable for urban gardens and food forests;5000-21780 sq. ft. suitable for gardens andfood forests; > 21780 sq. ft. suitable forurban farms and food forestsDetermine the areaunder tree canopypotentially suitable foragroforestryLandcover_Forested_PotentialFoodForestLandcover_SitesCanopy, 2009;Landcover_SitesSlope10, 2003;Landcover_SitesSensitiveArea,2012; Landcover_SitesImpervious, 2012The SitesSlope10, SitesSensitiveArea,SitesImpervious were merged together andthen dissolved to remove any overlap. Theresulting area was considered unsuitable foragroforestry, erased from theLandcover_SitesCanopy feature class,intersected with candidate sites and thenreported in sq. ft in the results dataset asForested_PotentialFoodForest.
Appendix C. Results TableSuitabilityCategoryReporting CategoryNumberof SitesCultivatableArea in AcresNotesPotentialCultivatableAreasuitable for cultivation 192 256.2 Out of 362 total Candidate Sitessmall community gardens 26 2.2 meets minimum area requirements forcommunity gardens, food forests 76 20.5 meets minimum area requirements forurban farms, food forests 90 233.5 meets minimum area requirements forunsuitable 170 0agroforestry 208 492Forested areas with 10% or less slope,outside of sensitive areas and impervioussurfaces and 2500 sq. ft or greaterSites with Cultivatable AreaTransportationAccessibility< .25 miles 143 196 straight line to nearest bus stop.25-.5 miles 40 31 straight line to nearest bus stopmedium or high atp score 167 228 4-11 low, 12-19 medium, 20-28 highhigh atp score 23 46 4-11 low, 12-19 medium, 20-28 highSoil Suitabilitypotential arsenic contamination 99 134 "safe", non-detect to 20.0 ppmpotential arsenic contamination 4 3.8"threat to public health", 100ppm orgreaterUSDA Farm Soil Rating 161 121 soils of statewide importance or betterEquity -Poverty40% or more of census tract at 200%FPL32 39sites are within census tracts meetingcriteriacensus tract at or below 80% FWMHHI43 59sites are within census tracts meetingcriteriaEquity –Ethnicity25-50% minority 144 190A weighted average of the percentminority population for all Census blockswithin a quarter mile of each site50-75% minority 8 11.6A weighted average of the percentminority population for all Census blockswithin a quarter mile of each site
26 | P a g eSuitabilityCategoryReporting CategoryNumberof SitesCultivatableArea in AcresNotesResidentialDensity4:1-8:1 38 32.1A weighted average of household unitsper acre for all Census blocks within a1/4 mile of each sitePresent UsePublic School 21 84Vacant (Multi-family) 7 7.6Land UseCategoryOpen Space 16 46Vacant 18 7.7Park and Ride 5 6.7OwnershipCity of Federal Way 104 107Federal Way School District 31 100Lakehaven Utility District 22 15.6King County Housing Authority 8 5.5
Appendix D. Sample Site ProfilesThe following site profiles are examples of how the public land inventory can be used toidentify sites for potential cultivation. Each profile includes a brief description of urbanagriculture potential, Google Earth satellite and street view imagery, and select sitecharacteristics.Site A) Potential Neighborhood Garden or Food Forest:High Point Park Open Space (Site 233)This small neighborhood site has 4,000 square feet of good soil for growing. Even forneighbors with land to grow vegetables at home, the site could provide an excellent space fora food forest containing fruit trees and edible shrubs.Key Site Characteristics City-owned 7,594 square feet total 4,310 cultivatable square feet 5-10% average slope Within ¼ mile of bus stop Low arsenic concentration andgood soil for cultivation
28 | P a g eSite B) Potential “Commuter Garden”Redondo Heights Parks and Ride (Site 17)This site has more than 70,000 square feet of cultivatable space. As a park and ride, it couldprovide convenient access for commuters to tend crops and harvest food as part of their dailyroutine.Key Site Characteristics County-owned 10 acres total 73,109 cultivatable square feet 0-5% average slope Within ¼ mile of bus stop In census tract at or below 80%of Federal Way medianhousehold income
29 | P a g eSite C) Potential Community Garden on Park LandWest Hylebos Wetlands Park (Site 32)This 100+ acre park includes about 7,000 square feet of potentially cultivatable land at theentrance seen below. In Seattle, the Rainier Beach Urban Farm and Wetlands is an example ofhow urban agriculture can complement nearby ecosystems and open space.Key Site Characteristics City-owned 101 acres total 32,000 cultivatable square feet 5-10% average slope Within ¼ mile of bus stop