Urban Tree Canopy Assessmentfor

The City of Tukwila, WA

Ian ScottDavey Resource Group

November 1, 2012

Why Tree Canopy?

Measure Quality

• Public Tree Inventory(i-Tree Streets)

• Private Tree Inventory(i-Tree Eco)

Measure Quantity• Tree Canopy Assessment

How Did We Do It?

Quality Control/Quality Assurance

• Kappa Coefficient(Tukwila = 0.9315)

• i-Tree Canopy (~23%)

Results

Canopy25%

Impervious

51%

Pervious

18% Ba

re Soil2%

Open Water5%

City WideThe city limits of Tukwila encompass an area of 9.99 square miles (6,396 acres). • 25% ‒ Canopy, 1,616 acres• 51% ‒ Impervious surfaces, 3,242 acres• 18% ‒ Pervious surfaces, 1,132 acres • 5% ‒ Open water, 299 acres• 2% ‒ Bare soils, 108 acres

Results

Regional Commercial

Manufacturing Industrial Center/Heavy

Light Industrial

Tukwila Urban Center

Heavy Industrial

Neighborhood Commercial Center

Manufacturing Industrial Center/Light

Tukwila Valley South

Commercial Light Industrial

Residential Commercial Center

High Density Residential

Regional Commercial Mixed Use

Mixed Use Office

Low Density Residential

Office

Medium Density Residential

CanopyOpen Water AcresPerviousBare SoilOpen Water

Results

% Land Cover By Zone

ResultsAcres of Land Cover By Zone

Residential Commercial CenterMixed Use Office

Neighborhood Commercial CenterOffice

Light IndustrialRegional Commercial Mixed Use

Regional CommercialMedium Density Residential

Light Manufacturing IndustrialHigh Density Residential

Heavy IndustrialTukwila Valley South

Commercial Light IndustrialTukwila Urban Center

Manufacturing Industrial Center/HeavyLow Density Residential

Canopy Open Water Acres

Pervious Bare Soil

Open Water

Results

Zone Class Canopy (%)

Impervious (%)

Pervious (%)

Bare Soil (%)

Open Water(%)

Medium Density Residential 51.33 35.10 13.50 0.05 -

Office 49.24 35.90 14.72 - -

Low Density Residential 47.44 21.95 28.51 1.43 0.60

Mixed Use Office 41.02 8.39 48.65 1.93 -

…. …. …. …. …. ….

Commercial Light Industrial 21.15 67.98 9.74 0.60 0.42

Tukwila Valley South 21.14 28.55 28.34 18.55 3.41

Manufacturing Industrial Center/Light 19.84 71.85 7.82 - 0.16

Neighborhood Commercial Center 13.19 69.91 16.77 - -

Heavy Industrial 10.92 80.78 6.44 0.34 1.51

Tukwila Urban Center 10.71 77.42 9.47 0.23 2.18

Light Industrial 9.89 80.71 8.12 0.68 0.60

Manufacturing Industrial Center/Heavy 9.28 71.61 12.87 1.84 4.23

Regional Commercial 8.58 80.52 9.60 1.01 -

Land Cover By Zone

ResultsCanopy in Parks Park Name Park Acres Canopy

AcresCanopy

PercentageSouthgate Park 4.96 4.96 100%Crystal Springs Park 8.48 8.29 98%

Pamela Drive Open Space 0.67 0.65 97%

Tukwila Park 6.39 5.84 91%Southgate Park 5.94 5.35 90%

Ikawa Park (Japanese Garden) 0.20 0.18 90%

Crystal Springs Park 2.55 1.79 70%Hazelnut Park 0.60 0.39 65%

… … … …

… … … …

Tukwila Community Center 12.75 3.24 25%

Riverton Park 4.88 1.21 25%Foster Golf Links 63.34 15.13 24%

Joseph Foster Memorial/Lee Philips Park 9.31 1.98 21%

Tukwila Pool 1.29 0.24 19%Duwamish Park 2.11 0.31 15%

57th Ave South Mini Park 0.38 0.05 13%

North Wind's Weir 2.58 0.07 3%GRAND TOTAL 265.07 100.87 38%

Results

Neighbor Cities

Canopy Context (%)

Bellevu

e

Kirklan

d

Merce

r Islan

d

Shorelin

e

Seatt

le

Tukwila

Renton

Tacoma

Bonney Lak

e

Port Ange

les

Vanco

uver

Portlan

d05

101520253035404550

3641 41

31

23 2529

13

43

27

18

32

Neighbor CitiesSeattle

Land Use

2010 Canopy (%)

Commercial 15.6

High Density Residential 32.5

Industrial 17.1

Low Density Residential 32.6

Resource Conservation 68.2

Public Right-of-Way 14.1

Land Use2011Canopy (%)

Medium Density Residential 51.33 Office 49.24 Low Density Residential 47.44 Mixed Use Office 41.02

Regional Commercial Mixed Use 37.47 High Density Residential 33.3

Residential Commercial Center 29.63 Commercial Light Industrial 21.15 Tukwila Valley South 21.14

Manufacturing Industrial Center/Light 19.84

Neighborhood Commercial Center 13.19

Heavy Industrial 10.92 Tukwila Urban Center 10.71 Light Industrial 9.89

Manufacturing Industrial Center/Heavy 9.28 Regional Commercial 8.58

Parks 38%

Land Use

2007 Canopy (%)

Single Family 25.7Multi-Family 17.1Commercial/Mixed Use 9.7Manufacturing 4.3Downtown 4.7Developed Park 25.5Major Institution 19.4Parks Natural Area 80.4

RentonTukwila

Setting Goals

Potential Canopy

City AcresExisting Acres

Existing %

Possible Acres

Possible%

6396 1615.77 25.26% 1040.91 41.54%

Setting Goals

Potential CanopyZone Class Zone Acres Existing Acres Existing % Possible Acres Possible%

Commercial Light Industrial 416.68 88.14 21.15% 39.77 30.70%

Heavy Industrial 151.13 16.51 10.92% 6.15 14.99%

High Density Residential 145.66 48.50 33.30% 15.94 44.24%

Lignt Industrial 51.59 5.10 9.89% 2.17 14.09%

Low Density Residential 1638.94 777.48 47.44% 384.99 70.93%

Manufacturing Industrial Center/Heavy 1033.73 95.94 9.28% 80.55 17.07%

Manufacturing Industrial Center/Light 99.34 19.71 19.84% 7.04 26.93%

Medium Density Residential 83.95 43.09 51.33% 11.37 64.87%

Mixed Use Office 34.20 14.03 41.02% 17.30 91.61%

Neighborhood Commercial Center 38.29 5.05 13.19% 6.42 29.96%

Office 49.72 24.48 49.24% 7.32 63.96%

Regional Commercial 69.34 5.95 8.58% 7.36 19.20%

Regional Commercial Mixed Use 66.77 25.02 37.47% 6.02 46.49%

Residential Commercial Center 5.67 1.68 29.63% 1.31 52.73%

Tukwila Urban Center 763.51 81.75 10.71% 71.55 20.08%

Tukwila Valley South 265.83 56.20 21.14% 124.65 68.03%

Communicating Value

I Tree VUE – Pollution Benefits by the Numbers

• Stored Carbon ~ 71,000 Tons $1.4M • Sequestered Carbon ~ 2300 Ton/yr $48K • Carbon Monoxide (CO) ~ 4.3 Ton/yr $4K• Nitrogen Dioxide (NO2) ~ 10 Ton/yr $89K• Ozone (O3) ~ 4.3 Ton/yr $240K• Sulfur Dioxide (SO2) ~ 8.5 Ton/yr $18K• Particulate Matter ~ 15.7 Ton/yr $94K

Yearly Benefit $423K

Communicating Value

Google Earth

• Exploring Potential Planting• Change in Time

Communicating Value

Communicating Value

Questions?