Objectives

This analysis is based on an exercise in ESRI’s MOOC program “Going Places with Spatial Analysis”. While the exercise is designed to be completed in arcgis online, a subscription is required hence my goal here is to replicate the analysis using simple Quarto dashboards in R. This is the first in a series of exercises I shall replicate.

A local development company is looking for optimal sites to build small mixed-use developments, in a city with a large amount of land already zoned for mixed-use development. The target demographic are people in their 20s and 30s for both the retail and rental units. They believe areas with larger rental markets offer more potential for clients who would be interested in the new rental units that would be available. To create innovative mixed-use developments with diversity and equity in mind, the goal is to select sites that comply with the affordable housing and equitable transportation policies.

Should the development company build a small mixed-use development in the municipality of Grisham? To answer this question, we need to know:

  1. how much area is zoned for mixed use development in Grisham
  2. where the high rental areas are (areas with above average rental units)
  3. in which of these high rental areas high numbers of people between the ages of 22 and 39 live (the distribution of 22-39 year olds)
  4. where people that require affordable rental housing live (areas with household income < $50,000)
  5. proximity to public transportation (being within 0.25 miles of the MAX Light Rail blue line?)
Data

The Grisham city boundary, zoning and public transport Layers are obtained from the ArcGIS Living Atlas of the World using their service links. Zoning data contains features on municipalities east of Portland while transportation data provided by TriMet contains bus, light rail and commuter rail service in the Portland, Oregon region. It includes the Metropolitan Area Express Light Rail which connects Portland City Center with Beaverton, Clackamas, Gresham, Hillsboro, Milwaukie, North/Northeast Portland and Portland International Airport. The Grisham housing blocks layer is enriched with the home occupancy (number of owner and rental units) and the median income per block, and the resulting shapefile is downloaded. These layers are owned by EsriTrainingSvc. We analyse these layers to answer the questions above.

All data layers are matched to the projection of the zoning data (EPSG: 4326) and the variables required to answer the development company’s questions: CITY, ZONING DESCRIPTION, ZONING, ACRES, AGE_22_39 (AGE_22_29 + AGE_30_39), RENTAL UNITS, MEDIAN INCOME, LIGHT RAIL and ABOVE AVG RENTAL AREAS (i.e RENTAL UNITS > mean(RENTAL UNITS)) are selected.

layers links
grisham_city_boundary_data https://services.arcgis.com/ue9rwulIoeLEI9bj/arcgis/rest/services/city_boundary1/FeatureServer/0
grisham_zoning_data https://services.arcgis.com/ue9rwulIoeLEI9bj/arcgis/rest/services/Gresham_Zoning/FeatureServer/0
grisham_block_group_data /Users/hitimana/Desktop/kwize/Kwiz Computing Technologies - Rebirth/GIS/esri/Going Places with Spatial Analysis - MOOC/2. Exercise 1- Understand and compare places- Mixed-use development/data/Block_Group_Enriched_with_Owner_and_Rental_Units_and_Median_Income/EnrichedLayer.shp
grisham_public_transport_data https://services.arcgis.com/ue9rwulIoeLEI9bj/arcgis/rest/services/MAX_Light_Rail/FeatureServer/0

Grisham City is grouped into 15 zones, each with one or more sub-classes (ZONING DESCRIPTION) as shown in Table 1 above.

ZONING ZONING DESCRIPTION Freq
8
CC Permits moderately scaled commercial; mixed-use; and residential uses. 2
CG General Commercial 24
CG Extensive Commercial 5
CG Exclusive Extensive Commercial 6
CG Urban General Commercial District 1
CG Permits commercial; mixed-use; and residential uses. 2
CN Neighborhood Commercial 10
CN Urban Local Commercial District 1
CO Transit Development - High density Civic 1
CO Transit Development - Medium density Civic 2
CO Transit Development 2
IH Heavy Industrial 5
IL Light Industrial 12
IMU Business Park (Mix of commercial and light industrial uses) 5
MFR1 Medium Density Residential - Civic (min 17 units/acre) 1
MFR1 Moderate Density Multi-Family Housing (12.1 to 24.2 units/acre) 50
MFR1 Moderate Density Multi-Family Housing (8.71 to 12.1 units/acre) 20
MFR1 Downtown Low-Density Residential. 1
MFR2 High Density Residential - Civic (min 24 units/acre) 1
MFR2 High Density Residential (Apartment Density of 20.26-60.08 units/acre) 10
MUC1 Office/Residential (Mix of office and moderate density residential) 13
MUC1 Central Urban Core - commercial/mixed use at about 17 units/acre. 1
MUC2 Downtown Moderate-Density Residential; densities from 17-30 units/acre. 3
MUC2 Downtown Transit - commercial; mixed use; and residential uses. 1
RRFU Urban Future District (minimum lot size = 20 ac.) 2
SFR2 Single family residential 18
SFR3 Single family residential 18

There are 18 mixed use zones (ZONING: “MUC1” or “MUC2”) totaling 517.38 Acres. Figure 1 maps layers for the city’s zoning categories and the areas zoned for mixed use development. From the summary table (Table 2), most of these blocks zoned for mixed use developments are small in size (Median Acreage < Mean Acreage) with larger mixed use lots near the city center and smaller lots towards the North-West.

Figure 1: Map of All Zoning Categories and Mixed use Zones in Grisham City
Table 2: Mixed Use Block sizes
vars n mean sd median trimmed mad min max range skew kurtosis se
ACRES 1 18 28.7433 45.6577 8.765 23.5787 7.9616 1.03 139.09 138.06 1.5999 0.7729 10.7616

The development company is interested in areas with a high number of renters/rental units, targeting renters aged between 22-39 years. The Grisham High Rent Areas layer in Figure 3 differentiates between the high rent (rental units > average) and low rent neighborhoods in Grisham, quantifying the existing rental units and the target population while the Where 22-39 year olds live in High Rent Areas of Grisham City layer identifies the percentage of the proportion of the target population within the high rental markets.

Figure 3: Map of population between 22-39 years in High Rent Areas in Grisham City

To comply with the affordable housing and equitable transportation policies, we ovelay a map of median household incomes < $50,000 (Affordable Housing Neighbourhoods layer) and a buffer of 0.25 miles around the MAX Blue Line light rail system (Proximity (0.25 Mile buffer) to the Blue rail Light Rail System layer) to identify locations that satisfy the 2 policies (Figure 4).

Figure 4: Map of Median Income < $50,000 in Grisham City along 0.25 miles of the Blue Line Light Rail System

Select your features of interest to visualize their interactions

Figure 6: Map intersecting qualifying features to Identify the 4 Optimal Plots for Small Mixed Use Development