rateofurbanization

THE RATE OF URBANIZATION AND FOREST HARVEST IN THURSTON COUNTY 1985-2000: 

THE RATE OF URBANIZATION AND FOREST HARVEST IN THURSTON COUNTY 1985-2000 Thurston Regional Planning Council 1985 Nisqually Delta Hawk’s Prairie 2000

Partial funding was provided through a grant from the Washington State Office of Community Development, Growth Management Program: 

Partial funding was provided through a grant from the Washington State Office of Community Development, Growth Management Program

What is Land Cover ?: 

What is Land Cover ? Land Cover categorizes the vegetation, water, natural surface, and cultural features on the land surface.

How is Change in Land Cover Monitored?: 

How is Change in Land Cover Monitored? Training a computer to look for differences over time in vegetation cover. Visually interpreting change in paired images.

Why Use Satellite Data?: 

Why Use Satellite Data? Cost Consistency Convenience

Rate of Forest Harvest: 

Rate of Forest Harvest Pink: very recent harvests (0-5 years) Light Green: recent harvests with some vegetation regrowth (5-15 years) Dark Green: intact forest lands 2000 Landsat Satellite Data. Area shown is in Capitol Forest, slightly north of the Black and Chehalis Rivers.

Inventory of Forest Lands: 

Inventory of Forest Lands 197,800 acres of Commercial Forest Lands 132,900 in Private Ownership 64,900 in Public Ownership (Capitol Forest) Addition Forest Lands on the 17,000 acre Fort Lewis Military Reservation Remainder in other non-commercial ownership 282,400 acres 269,800 acres By Land Cover By Ownership There are approximately 470,000 acres of land in Thurston County

Slide8: 

Distribution of Forest Lands There are 470,000 acres of land in Thurston County Forest lands are not only found in the rural county. 3 percent of forest lands, as measured by land cover, are found within existing city limits, these include city parks, and tracts of undeveloped land. A further 3 percent of forest lands are found in urban growth areas.

The Harvest Cycle 1985-2000: 

The Harvest Cycle 1985-2000 There are 470,000 acres of land in Thurston County 56,000 acres were in the forest harvest cycle in the last 15 years or 20 percent of the county’s total forest land area This is an approximate annual harvest rate of 4,000 acres 98 percent of harvest cycle activity (in acres) occurs in the rural county. These figures do not include forest to urban conversions of total harvested acres Distribution

What is the Harvest Cycle?: 

What is the Harvest Cycle? The harvest cycle is the change from forest cover to clear cut or partial cut, to seedlings and shrub cover, and finally back to forest cover. In Thurston County, approximately 75 percent of harvest areas are re-forested within 10-15 years of harvest.

Rate of Urbanization: 

Rate of Urbanization Green: vegetation Pink: built features and bare soils Satellite images (1985 and 2000) of Hawk’s Prairie Region of Lacey with city and urban growth area boundaries overlaid. 1985 Nisqually Delta Hawk’s Prairie 2000

In Thurston County between 1985 and 2000 …: 

In Thurston County between 1985 and 2000 … Population increased by 70,000 people 32,000 Building Permits were issued More than 48,000 jobs were created Over 15 million square feet of industrial or commercial building space was added 32,000 acres of intact forest lands, agriculture lands, or shrub vegetation were converted to urban lands

The Urban Landscape: 

The Urban Landscape Contains more than just buildings. 2000 aerial photo of a subdivision in rural Thurston County

The Urban Landscape: 

The Urban Landscape 17 percent built features, 21 percent forests or trees, and 62 percent lawns, shrubs, and other vegetation. Urban landscapes created in the last 15 years are composed of: lawns, shrubs, and other vegetation

What type of land is undergoing urban conversions?: 

What type of land is undergoing urban conversions? 57 percent were intact forest lands, 30 percent were agricultural lands, and 13 percent were shrub lands or lands cleared prior to 1985. Of the urban landscapes created in the last 15 years, measured by acres: More than 32,000 acres were converted to urban landscapes between 1985 and 2000

Where are urban conversions occurring?: 

Where are urban conversions occurring? 15 percent in the Cities, 15 percent in the unincorporated Urban Growth Areas; and 70 percent in the rural county. Growth is measured as total acres consumed

Built (Impervious) Surfaces: 

Built (Impervious) Surfaces Downtown Olympia Capitol Campus

Built (Impervious) Surfaces: 

Built (Impervious) Surfaces Built land cover has increased to 29 percent of the total land area in Thurston County cities It is much lower in the Urban Growth Areas and rural county

Why is this Important?: 

Why is this Important? The scientific community is beginning to recognize a relationship between stream health and land cover characteristics Source: Arnold, 1996.

The Relationship of Land Cover and General Water Quality in Thurston County: 

The Relationship of Land Cover and General Water Quality in Thurston County Each set of diamonds represent a single Thurston County basin. Note: Paired data points represent 1985 and 2000 data. In all cases, 1985 land cover is characterized by higher forest cover and lower urban cover relative to 2000 land cover 1985 2000

What’s Next: 

What’s Next Continue working with Stormwater Utilities of Thurston County, Lacey, Olympia and Tumwater to integrate data into hydrologic modeling efforts. Generate an impervious surface analysis module for the next population and employment forecast. Continue working with local Watershed groups, Public Health, and Planners.