Electric System Serving Pierce County Current system and future investments Janet Olsen Steve Botts Project Manager Real Estate t / Rights-of-Way April 13, 2011
Presentation overview Information requested at previous meeting Typical 230 kv construction: pole height, span length, easement width PSE operating rights and uses under power lines Underground transmission: easement width; termination structures and vault spacing Electric and magnetic fields, science and current research Drew Thatcher, Radiation Expert with Washington Department of Health Transmission siting process and routing considerations 2
Right-of-way width: typical
Underground transmission lines Easement or roadway 30-35 Vaults every 2,000 feet : 20 L x 10 W x 8 D Termination structures - each end Cost participation with jurisdiction (city or county) Underground and overhead transmission lines Estimated cost comparison Construction and relocation Operation & Maintenance ] Underground $5-11 million per mile $300 per mile per year Overhead $500k-$1 million per mile $1,100-1,900 per mile per year
Durable operating rights: easements or fee Durable operating rights are needed for 230 kv lines. Continuous reliability and capacity on the 230 kv system is essential. Power lines on city or county roadway property are subject to relocation which can take lines out of service during construction. PSE seeks to obtain easements or fee ownership of 230 kv power line corridors.
Compatible uses in PSE easements PSE reviews proposed ROW uses on a case-by-case basis Examples of typically allowable activities (conditions apply): Biking or hiking trails Parking lots Fixtures, signs or landscaping with a mature height of less than 15 feet Greenbelt areas and parks Agriculture Non-metallic fences Examples of typically prohibited activities: Buildings and other structures Anything that will impede access for line maintenance Septic tanks and drain fields Swimming pools Wells
Easement considerations: temporary and permanent Access for construction, maintenance and vegetation management Staging areas at each pole location for heavy equipment
Co-location of power lines in existing corridors State routes Power lines not permitted on limited access highways. Siting on other state routes subject to franchise and relocation upon notification City or county roads Subject to franchise and relocation upon notification Railroads Generally, power lines parallel need to be 50 distant from tracks Crossings are allowed by permits, which are revocable
Property rights for a safe power line corridor: vegetation management Keeping wire and border zones clear around transmission i lines is the most effective way to reduce tree-related power outages For 230 kv Lines: NERC Standard calls for removal of trees with a mature height over 15 feet in Wire zone and Border zone
Transmission line noise Transmission line noise includes corona, insulator, and Aeolian noise. Corona noise results from the breakdown of air into charged particles in a high h electric field. Louder during high h humid environments and heavy rain. Typically 40 to 50 dba close to transmission lines but can be as much as 60 dba during wet weather. Insulator noise not dependent upon weather. Aeolian noise caused by wind blowing through conductors and other structures. 10
Typical sound levels
A comparison of electric and magnetic fields
Background on EMF studies Epidemiology the study of exposures to humans Animal and laboratory studies Is there a plausible biological explanation?
Public health summary EMF is a consequence of using power in our lives WHO concludes that magnetic fields and health risks are not established nor are they supported by laboratory studies The public exposure limit is 833 mg and exposures are more than 100 times less than the recommended exposure limits
Route selection process
Line siting considerations Constructability Environmental impacts Existing utilities Maintenance and operation Permitting Public input Reliability Rights of way Types of property 17
230 kv power line engineering and design Typical Pole types: Wood Steel brown or silver No phone, cable tv or lower-voltage lines on poles Single circuit line 3 wires and fiber optic cable
Study areas: East Central West
White River Transmission Substation
East Corridor CONCEPTUAL ROUTE: North of SR 410, parallel to existing corridors: PSE Transmission Williams Natural Gas Pipeline Corridor Roadways South of SR 410, through Sumner- Orting Valley
East Corridor Critical Constraints: Dense residential areas Construction and maintenance is difficult on steep slopes Requires extensive tree removal to meet 230 kv vegetation clearing standards Property owners in Sumner/Orting Valley have already been affected by a PSE transmission line project 22
East Route - south of White River Station Residences just south of White River Station Existing 115 kv line Existing 115 kv line on 166 th St E
East Route Cross country near 164 th AeE Ave. Sumner- Tapps Hwy
Central Corridor CONCEPTUAL ROUTE: Generally parallel with existing transmission lines heading west from White River transmission substation Uses existing 75 easement between Burlington Northern Railroad and East Valley Highway Existing lines on both sides of Valley Ave in Sumner Central Business District Uses existing 80 PSE fee-owned right- of-way on east side of SR 162
Central Corridor Critical Constraints: Wetland depression on north end of East Valley Highway Downtown Sumner has zero building setbacks in areas Residences and businesses along Valley Avenue would be affected Vegetation clearing to 230 kv standards may impact landscape trees Widening of SR 162 would be forced to west side of highway or cost of power line relocation falls to WSDOT / taxpayers 26
Central Route, north end Looking east up the hill to White River Station Wetland depression: poles located between East Valley Hwy and railroad track
Central Route Valley Avenue Existing business district on Valley Ave Transmission lines on both sides of Valley Ave
Example of 230 kv construction Example of 230 kv construction ction on city street in West Seattle 29
Central Route SR 162, south of SR 410 Looking South from Pioneer Way Aerial View two PSE transmission lines on east side of SR 162
Conceptual design: SR 162, S of Pioneer Way
West Corridor CONCEPTUAL ROUTE: Would be built behind warehouse area Would run through Cannery Commercial District Crosses over SR 410 and Puyallup River Parallels Pioneer Way / Foothills Trail
West Corridor Critical Constraints: Construction next to drainage stream (warehouse area) is difficult Threading the needle through commercial district, over SR 410, Puyallup River and railroad trestle requires complex design and additional poles Proximity to sensitive areas: Puyallup River Shorelines and Channel Migration Zones Vegetation clearing to 230 kv standards will require some tree removal for river crossings, possibly Foothills Trail corridor 33
West Route Warehouse District (conceptual)
West Route west side of Warehouse District
West Route - Sumner The Cannery / Commercial area looking west Sumner Wastewater Treatment Plant, looking north toward SR 410
West Route South of SR 410 New Shaw Road Extension 134 th Avenue 134 Avenue East near Annexation area
West Route Foothills Trail Off Pioneer Way, looking south (Existing 115 kv line)
Conceptual design: Foothills Trail Corridor
Alderton Transmission Substation
BREAK 41
Next Steps Introduce the project to the public in Open House - May 5, 2011, 5 p.m. at Sumner Public Library Continue working with Community and Advisory group to refine transmission line route alternatives Inform stakeholders and property owners of preferred route Begin engineering and environmental studies, permitting and design Construction is anticipated to begin in 2013 42
Contact us Janet Olsen Gary Nomensen Project Manager Government & Community 425-462-3912 Relations Manager 253-476-6403 info@psepierce230kv.com www.pse.com/pierce230kv 43