Response to Council Inquiry Denny Substation Site Co-Development Report April 1, 2013 ALLEY 24 SCCA HOME FEATHERED FRIENDS BREWSTER APARTMENTS DAVID COLWELL APARTMENTS MIRABELLA PARCEL 3 EXISTING UNDERGROUND TRANSMISSION LINE PONTIUS AVE PARCEL 2 PARCEL 1 EXISTING UNDERGROUND TRANSMISSION LINE DENNY WAY PROPOSED | 1200 STEWART SITE & CONTEXT DIAGRAM Current Context Diagram Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Page 1 POTENTIAL FUTURE UNDERGROUND TRANSMISSION LINE TO CANAL SUBSTATION EXISTING UNDERGROUND TRANSMISSION LINE TO BROAD SUBSTATION SUBSTATION EXISTING UNDERGROUND TRANSMISSION LINE TO EAST PINE SUBSTATION NEW DENNY WAY UNDERGROUND TRANSMISSION LINE TRANSMISSION TO MASSACHUSETTS SUBSTATION DISTRIBUTION DISTRIBUTION CONCEPT Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Distribution Concept Diagram Page 2 P3 AERIAL PERSPECTIVE SUBSTATION P1 P2 NORTH SOUTHWEST CORNER PERSPECTIVE SITE PLAN Co-Development Concept 1 (BASELINE) Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Page 3 DESCRIPTION & COST: PARCELS 1 & 2 (SUBSTATION): PARCELS 1 & 2: CONSTRUCTION COST 1) • Substation - One level above grade $164,000,000 PARCEL 3: PARCEL 3: LAND VALUE (1) • Mixed-use commercial or residential ($5,400,000) TOTAL COST (PE# 7757): $158,600,000 SCHEDULE: ENERGIZED Q3 OF 2016 MEETS TARGET SCHEDULE OBSERVATIONS: COMMUNITY • Provides public amentity & open space resulting from vacating Pontius • Lowest neighborhood construction impacts - 2,300 truck loads CONSTRUCTION & OPERATIONS • Lowest operational & construction complexity DEVELOPMENT • Maximizes opportunity for future development on parcel 3 • If development is concurrent or is considered part of the substation project objective, then the schedule impact will be a delay of approxi- mately 9-12 months, resulting in the substation being energized in Q3 of 2017. DENNY WAY NOTES COMMON TO ALL SCHEMES: (1) 2017 appreciated land value based on information provided by Heartland LLC NOTE: * Development massing based on the proposed rezoning for South Lake Union SITE PERSPECTIVE STREET VACATION REQUIRED ** Concept 1, the “Baseline”, is the one story alternative that best represents the preference voiced by the public Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Co-Development Concept 1 (BASELINE) Page 4 210’-0” RESIDENTIAL OR COMMERCIAL 40’-0” UTILITY TUNNEL EASEMENT DEVELOPMENT POTENTIAL P3 UNDERGROUND 280’-0” PARKING WATER SITE SECTION TABLE SUBSTATION P1 P2 RESIDENTIAL OR COMMERCIAL DEVELOPMENT POTENTIAL NORTH SUBSTATION PERSPECTIVE SITE PLAN Co-Development Concept 2 Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Page 5 DESCRIPTION & COST: PARCEL 2 (SUBSTATION): PARCEL 2: CONSTRUCTION COST MASSING OF POTENTIAL • Substation - One level above grade, one level $203,700,000 RESIDENTIAL below grade DEVELOPMENT PARCEL 1: PARCEL 1: LAND VALUE (1) • Residential high-rise or commercial mid-rise ($17,500,000) PARCEL 3: PARCEL 3: LAND VALUE(1) • Mixed-use commercial or residential ($5,400,000) TOTAL COST (PE# 7757): $180,800,000 DELTA FROM BASELINE: $22,200,000 MASSING OF POTENTIAL DEVELOPMENT SCHEDULE: ENERGIZED Q3 OF 2017 DELTA FROM BASELINE APPROX. 9-12 MONTHS OBSERVATIONS: COMMUNITY • Limited public amenity, open space or landscaping • Intermediate neighborhood construction impacts - 8,000 truck loads • Accoustical mitigation issues CONSTRUCTION & OPERATIONS • Below water table, lifetime water management risk • Requires utility tunnel • Intermediate operational & construction complexity DEVELOPMENT • Maximizes development potential on parcels 1 and 3 DENNY WAY NOTE: SITE PERSPECTIVE NO STREET VACATION REQUIRED Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Co-Development Concept 2 Page 6 220’-0” RESIDENTIAL OR COMMERCIAL 40’-0” UTILITY TUNNEL EASEMENT DEVELOPMENT POTENTIAL 340’-0” P3 UNDERGROUND PARKING WATER SITE SECTION TABLE OPEN SPACE P1 P2 RESIDENTIAL OR COMMERCIAL DEVELOPMENT POTENTIAL NORTH SUBSTATION PERSPECTIVE SITE PLAN Co-Development Concept 3 Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Page 7 DESCRIPTION & COST: PARCEL 2 (SUBSTATION): PARCEL 2: CONSTRUCTION COST MASSING OF POTENTIAL • Substation - One level below grade $263,700,000 RESIDENTIAL • Public open space DEVELOPMENT PARCEL 1: PARCEL 1: LAND VALUE (1) • Residential high-rise or commercial mid-rise ($18,500,000) PARCEL 3: PARCEL 3: LAND VALUE (1) • Mixed-use commercial or residential ($5,800,000) TOTAL COST (PE# 7757): $239,400,000 DELTA FROM BASELINE: $80,800,000 MASSING OF POTENTIAL DEVELOPMENT SCHEDULE: ENERGIZED Q3 OF 2018 DELTA FROM BASELINE APPROX. 18-24 MONTHS OBSERVATIONS: COMMUNITY • Provides opportunity for public amenity & open space but requires sale of land to Parks Department in order to maintain grounds • Highest neighborhood construction impacts - 12,400 truck loads • Accoustical mitigation issues CONSTRUCTION & OPERATIONS • Below water table, lifetime water management risk • Requires utility tunnel • Highest operational & construction complexity • Intermediate amount of excavation DEVELOPMENT • Maximizes development potential on parcels 1 and 3 DENNY WAY • Provides opportunity for heat recovery NOTE: SITE PERSPECTIVE NO STREET VACATION REQUIRED Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Co-Development Concept 3 Page 8 120’-0” 20’-0” 90’-0” RESIDENTIAL OR COMMERCIAL 40’-0” UTILITY TUNNEL EASEMENT DEVELOPMENT POTENTIAL 340’-0” RESIDENTIAL OR P3 UNDERGROUND COMMERCIAL PARKING DEVELOPMENT WATER SITE SECTION POTENTIAL TABLE SUBSTATION P1 P2 RESIDENTIAL OR COMMERCIAL DEVELOPMENT POTENTIAL NORTH SUBSTATION PERSPECTIVE SITE PLAN Co-Development Concept 4 Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Page 9 DESCRIPTION & COST: PARCEL 2 (SUBSTATION): PARCEL 2: CONSTRUCTION COST MASSING OF POTENTIAL • Substation - Two levels above grade, one & LAND VALUE RESIDENTIAL level below grade $257,100,000 DEVELOPMENT • Residential high-rise or commercial mid-rise ($20,100,000) PARCEL 1: PARCEL 1: LAND VALUE (1) • Residential high-rise ($16,600,000) PARCEL 3: PARCEL 3: LAND VALUE (1) • Mixed-use commercial or residential ($5,400,000) MASSING OF POTENTIAL RESIDENTIAL DEVELOPMENT TOTAL COST (PE# 7757): $215,000,000 DELTA FROM BASELINE: $56,400,000 MASSING OF POTENTIAL DEVELOPMENT SCHEDULE: ENERGIZED Q3 OF 2018 DELTA FROM BASELINE APPROX. 18-24 MONTHS OBSERVATIONS: COMMUNITY • No opportunities for public amenity & open space • Intermediate neighborhood construction impacts - 6,100 truck loads • Accoustical mitigation issues • Negative visual impact for neighbors • Close substation equipment proximity to residential units CONSTRUCTION & OPERATIONS • Below water table, lifetime water management risk • Highest operational & construction complexity • Intermediate amount of excavation • Increased amount of service infrastructure • Risk to substation from adjacent future construction DENNY WAY • No parking for maintenance • Increased risk to the substation during co-development construction • Requires utility tunnel DEVELOPMENT • Provides development potential on parcels 1, 2, and 3 NOTE: SITE PERSPECTIVE NO STREET VACATION REQUIRED Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Co-Development Concept 4 Page 10 MASSING OF POTENTIAL RESIDENTIAL DEVELOPMENT 120’-0” 20’-0” 90’-0” RESIDENTIAL OR COMMERCIAL 40’-0” UTILITY TUNNEL EASEMENT DEVELOPMENT POTENTIAL SUBSTATION 340’-0” RESIDENTIAL OR P3 UNDERGROUND COMMERCIAL PARKING DEVELOPMENT WATER SITE SECTION POTENTIAL TABLE P1 P2 RESIDENTIAL OR COMMERCIAL DEVELOPMENT POTENTIAL NORTH SUBSTATION PERSPECTIVE SITE PLAN Co-Development Concept 5 Response to Council Inquiry Denny Substation Site Co-Development Report | April 1, 2013 Page 11 DESCRIPTION & COST: PARCEL 2 (SUBSTATION): PARCEL 2: CONSTRUCTION COST MASSING OF POTENTIAL • Substation - Access area above grade, three & LAND VALUE RESIDENTIAL levels below grade $334,000,000 DEVELOPMENT • Residential high-rise or commercial mid-rise ($28,400,000) PARCEL 1: PARCEL 1: LAND VALUE (1) • Residential high-rise or commercial mid-rise ($16,600,000) PARCEL 3: PARCEL 3: LAND VALUE (1) • Mixed-use commercial or residential ($5,400,000) MASSING OF POTENTIAL RESIDENTIAL DEVELOPMENT TOTAL COST (PE# 7757): $283,600,000 DELTA FROM BASELINE: $125,000,000 MASSING OF POTENTIAL DEVELOPMENT SCHEDULE: ENERGIZED Q3 OF 2019 DELTA FROM BASELINE APPROX. 27 - 36 MONTHS OBSERVATIONS: COMMUNITY • Highest neighborhood construction impact - 12,700 truck loads • No opportunities for public amenity & open space • Significant accoustical mitigation issues • Negative visual impact to neighbors CONSTRUCTION & OPERATIONS • Below water table, lifetime water management risk • Highest operational & construction complexity • Deepest excavation • Increased amount of service infrastructure • Risks to substation from adjacent future construction • Underground transformers require dependency redundant mechanical cooling - adding failure lifetime management risk • No on-site parking for maintenance • Requires utility tunnel DEVELOPMENT • Maximizes development potential on parcels 1, 2, and 3 • Provides opportunity for heat recovery • Requires co-design on Parcel 2 NOTE: SITE PERSPECTIVE NO STREET VACATION REQUIRED Response to Council Inquiry Denny Substation Site Co-Development