The Current and Future Impact of Community Gardens in the City of BerkeleyYvonne Chan Benjamin Kopania Jie Zhou Dec 8th, 2017

LD ARCH & GEOG C188 Final ProjectInstructor: Prof. John Radke GSI: Michelle Wray Nimisha Wasankar Yang Liu

Introduction Our client is the Berkeley Food Institute (BFI), a local organization that seeks to expand access to fresh food while promoting sustain-able and equitable food production. These goals require that current food systems are transformed to cultivate alternative and regionalized “agri-food networks” that increase local food sovereignty. One prima-ry objective of the BFI is to fill existing gaps of knowledge through re-search in order to inform policymakers. This project seeks to aid the BFI in their research by performing an analysis that will demonstrate the current and potential future impact of community gardens in serv-ing the demand for local food in Berkeley.

Image Resource: https://inhabitat.com/tag/sustainable-farming/

Data Discovery DEM

VectorSoil TypeDisadvantage CommunitiesBike?Streets?Parks?DensityLanduse

Toxic SitesLandslidesSoil?

Contour Lines

Service Area Analysis

Export Service Area Polygons

Location Alloca-tion Analysis

Load Berkeley Network

Load Locations of Existing Gardens

TIN Model

Gentle Slope

Add Weight

Add Weight

Add Weight

Union

Union

Union

Opportunities Factors

Constraints Factors

Composite Opportunities Map

Suitability Map

Drape on TIN Model

Select Best Sites

Location Alloationwith Existing gradens

Maxium Market Share

Maxium Market Share

Calculate % of Populatin ServedCurrent % of

Populatin Served

Composite Constraints MapSteep Slope

Data Discovery DEM

VectorFertile SoilDisadvantage CommunitiesBike BovelavardStreets ProximityParks ProximityDensity AreaLanduse

Toxic SitesLandslidesInfertile Soil

Contour Lines

Service Area Analysis

Export Service Area Polygons

Location Alloca-tion Analysis

Load Berkeley Network

Load Locations of Existing Gardens

TIN Model

Gentle Slope

Add Weight

Add Weight

Union

Union

Union

Opportunities Factors

Constraints Factors

Composite Opportunities Map

Suitability Map

Drape on TIN Model

Select Best Sites

Location Allocationwith Existing gradens

Maximum Market Share

Maximum Market Share

Calculate % of Population ServedCurrent % of

Population Served

Composite Constraints MapSteep Slope

Constraints

Layer Constraint Weight

Toxic Sites 500 ft buffer -3

Steep Slopes Slopes > 8.5 degrees -2

Landslides 100 ft buffer -1

Current Gardens Within 1 minute service area -2

Soil Unsuitable for Farming (Vertisols)

-1

Opportunities

Layer Opportunity Weight

Gentle Slopes Slopes <= 5 degrees 1

Soil Fertile Soils (Alfisols and Mollisols)

1

Bicycle Boulevards 300ft Buffer 1

Streets 100ft Buffer 1

Parks 500ft Buffer 1

Population Density Greater than 15000, 500ft Buffer

1

Disadvantaged Communities CalEnviroScreen disadvantage percentile 1-30% (lowest scores), 31-55%, 56-80%

0, 1, 2

Landuse Vacant residential and commercial lots

2

Constraints

Layer Constraint Weight

Toxic Sites 500 ft buffer -3

Steep Slopes Slopes > 8.5 degrees -2

Landslides 100 ft buffer -1

Current Gardens Within 1 minute service area -2

Soil Unsuitable for Farming (Vertisols)

-1

Opportunities

Layer Opportunity Weight

Gentle Slopes Slopes <= 5 degrees 1

Soil Fertile Soils (Alfisols and Mollisols)

1

Bicycle Boulevards 300ft Buffer 1

Streets 100ft Buffer 1

Parks 500ft Buffer 1

Population Density Greater than 15000, 500ft Buffer

1

Disadvantaged Communities CalEnviroScreen disadvantage percentile 1-30% (lowest scores), 31-55%, 56-80%

0, 1, 2

Landuse Vacant residential and commercial lots

2

Opportunities WeightConstraints Weight

_̂_̂

Datum & Projection: NAD83 CA State Plane Zone IIIDate: December 8, 2017

Authors: BK, YC, JZ

Berkeley Urban Gardens Suitability AnalysisGarden Opportunities

_̂ Most Suitable Sites

Berkeley BoundaryGardens_SuitabilityTotal Weight

-5-4-3-2-10123456789 Ü0 0.7 1.4 2.1 2.80.35

Miles

!8

!8

!8

!8

!8!8

Datum & Projection: NAD83 CA State Plane Zone IIIDate: December 8, 2017

Authors: BK, YC, JZ

Ü

Potential Market Share of Existing and Proposed Gardens

Berkeley Gardens & Demand

!8 Existing and Potential Gardens

Demand Lines

Demand Points

Berkeley boundary

0 0.7 1.4 2.1 2.80.35Miles

!8

!8

!8

!8

Datum & Projection: NAD83 CA State Plane Zone IIIDate: December 8, 2017

Authors: BK, YC, JZ

Ü

Market Share of Existing GardensBerkeley Gardens & Demand

!8 Existing Gardens

Demand Lines

Demand Points

Berkeley boundary

0 0.7 1.4 2.1 2.80.35Miles

Problem Statement In our analysis, we aim to find the most suitable locations in Berke-ley for new community gardens, approximate the current market share of existing gardens in Berkeley, and calculate the market share increase that would result by the addition of new gardens. In order to define and select “suitable” locations, we combined a mixture of geo-physical, urban design, and demographic variables to pragmatically and equitably cite new garden locations.

MethodsWe achieved this through three modeling techniques:

1)TIN Model• Created a TIN model from USGS digital elevation model• Utilized model to calculate slope as a variable for an opportunity

and constraint layer

Datum & Projection: NAD83 CA State Plane Zone IIIDate: December 8, 2017

Authors: BK, YC, JZ

Berkeley Urban Gardens Composite Constraints

Garden ConstraintsBerkeley Boundary

constaint weight-7-6-5-4-3-2-10

Ü 0 0.7 1.4 2.1 2.80.35Miles

Datum & Projection: NAD83 CA State Plane Zone IIIDate: December 8, 2017

Authors: BK, YC, JZ

Berkeley Urban Gardens Composite Opportunities

Garden OpportunitiesBerkeley Boundary

Opportunities Weight123456789

Ü 0 0.7 1.4 2.1 2.80.35Miles

Findings and ConclusionCurrent population of Berkeley served by existing community gardens (%): 20.6%Potential population served by existing and proposed gardens (%): 30.9%Potential increase in access to gardens (%): 10.3%

With a potential 10% increase of individuals with access (here defined as within a 1-minute impedance area) to com-munity gardens, our findings suggest that there remains significant work in order for the City of Berkeley to enable its residents to have more sovereignty and control over city-grown food. Due to the city’s growing population and increasing density, it is vital that residents have access to green space; not only can this green space serve recreational purpos-es, but it can also enable vulnerable communities to affordably access nutritious food. We have concluded that with the space limitations of Berkeley, improving the transportation network, and thus accessibility, of the city could significantly increase the accessibility of community gardens.

Limitations:The primary limitations of our analysis were online access to geographic data and accuracy of impedance timing of the Berkeley network. Additional community engagement is also necessary to confirm the suitability of our selected sites.

For our initial market share analysis we used an im-pedance of 1 minute, which corresponded to our con-straint weight factor for the 1 minute service area of existing gardens. The resulting market share percent-age was 20.6%.

For our final market share analysis we included the orig-inal existing gardens and the two most suitable sites. The resulting market share percentage was 30.9%.

The results of our suitability analysis showed two sites in Berkeley that were the most suitable, as symbolized by the blue stars. We then used the feature to point tool to convert the top two sites to points in order to perform a loca-tion-allocation network analysis on them.

2) Composite suitability map• Utilized ArcGIS proximity tools to process opportunity and constraint factor layers• 3) Service area and point-to-point location allocation network analyses • Performed service area network analysis with an impedance of 1 minute intervals to generate a

constraint layer that will keep our selected sites out of the service area of current gardens• Performed location-allocation analysis to calculate market share of existing gardens • Performed location-allocation analysis to calculate total market share of current and proposed gar-

dens

Suitability Analysis

Network Analysis

Flow Chart

TIN Model

Data Sources:CalEnviroScreen Disadvantaged Communities:https://oehha.ca.gov/calenviroscreen/report/calenviroscreen-30

National Cooperative Soil Survey: https://www.arcgis.com/home/item.html?id=40778f761b8845e29c3eae8016404957

City of Berkeley Open Data Portal: https://data.cityofberkeley.info/browse?limitTo=maps&utf8=%E2%9C%93

USGS National Map Viewer: https://viewer.nationalmap.gov/basic/

Berkeley Existing Garden Locations:https://communitygarden.org/find-a-garden/?garden-search=Berkeley&distance=100

LD ARCH/GEOG C188 Labs 3 & 7 geodatabases and Berkeley/Oakland network

Legendno_aspect_suit_testsuit_wt

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

7

8

9

B_boundary