replacing an existing elevated storage tank on the same site...april 13, 2015 eric williams, pe 2015...
TRANSCRIPT
April 13, 2015Eric Williams, PE
2015 North Carolina Spring ConferenceNC AWWA-WEA
Replacing an Existing Elevated
Storage Tank on the Same Site
Existing Facilities
Maintenance Issues
Tank Alternatives
Challenges
Bid Challenges
Tank Construction
Tank Demolition
Construction Costs
Project Location
Project Location
01 Existing Facilities
2 Inch -12 Inch Water Lines
Materials Including PVC, Ductile Iron and Asbestos Cement
3 Master Meters
2 Elevated Storage Tanks
Existing Facilities
Constructed in 1998
Capacity – 250,000 Gallons
Style – Single Pedestal
Contractor – Brown Steel Contractors
West End Elevated Storage Tank
Constructed in 1973
Capacity – 200,000 Gallons
Style – Leg
Overflow Elevation – Approximately
2.2 Feet Lower than West End Tank
Contractor – Brown Steel Contractors
East End Elevated Storage Tank
02 Maintenance Issues
Tank in Need of Painting
Repainting would Require Complete Shrouding
Drip Line of Tank Extended Over 2 Adjacent Properties
East End Storage Tank Maintenance Issues
03 Tank Alternatives
Repaint and Repair Existing Tank
oCosts were Estimated at $500,000-$600,000 (Lead Based Paint)
oTank Would Still Be 40+ Years Old
Build a New Tank
oCan Increase Capacity
oCan Match West End Overflow Elevation
oCan Match Tank Style
oFuture Maintenance Less Costly
East End Storage Tank Alternatives
04 Challenges
New Tank Construction
Close Proximity of Homes
Pile Installation
Painting
Telecommunications Facilities
Demolition of Existing Tank
Resort/Vacation Destination –
Construction Schedule
Restrictions
Challenges
Challenges - Tank Site
05 Bid Challenges
Planned to Bid Tank Construction and Tank Demolition Separately
Only One Bid Received on Bid Day
Only One Bid Received on the Rescheduled Bid Day
Bid not Submitted by a Tank Contractor – A. C. Schultes
Bid Received Exceeded Budget
Able to Negotiate a Lower Price
Negotiations Included Adding Tank Demolition
Bid Challenges
06 Tank Construction
Water Line Installation
12-Inch Water Line
Design was to Cut In New Tee
Existing Isolation Valve Would not
Hold
Tank Construction
Foundation Installation
Driven 12-Inch Steel H Piles
Minimum Depth Required - 40 Feet
Monitored Vibration at Adjacent Homes
Noise Restrictions (8:00 am – 8:00 pm)
Pile Cap – 4 Feet Thick by 2.5 Feet
Wide
24 – 2” Anchor Bolts by 3 Feet 4 Inches
Long (To Extend 7 Inches Above
Concrete)
Tank Construction
Structure by Caldwell Tanks
Challenges
oClose Proximity of Homes
oTotal Site – Less than ½ Acre
oStorage Space for Steel
Components
oExisting Tank
oTelecommunications Structures
Tank Construction
Structure
Single Pedestal
Complaints/Damage to
Private Property
Tank Construction
Painting
Shrouding Required –
Tightly Woven Nylon
Windy Conditions –
15 mph Maximum
Summer Season
Restrictions
Tank Construction
Shrouding
Outriggers
Extensive Cabling
Equipment at Base of Tank for Raising and
Lowering Shroud
Tank Construction
Paint by Tnemec
Interior (Dry) – 2 Coat System
o Shop Prime – 5.0 mils Series N-140 Epoxy
o Stripe Coat – 5.0 mils Series N-140 Epoxy – For all Seams
and Abraded Areas
o Finish Coat – 5.0 mils Series N-140 Epoxy – Stripe Coat
then Full Coat
Interior (Wet) – 3 Coat System
o Shop Prime – 3.0 mils Series 94 Hydro-Zinc
o Stripe Coat – 3.0 mils Series 94 Hydro-Zinc – For all
Seams and Abraded Areas
o Finish Coat –
• 5.0 mils Series N-140 Epoxy – Stripe Coat to all Weld Seams,
Edges, Corners, Bolts and Nuts – Tank White
• 5.0 mils Series N140 Epoxy – Beige Color
• 5.0 mils Series N140 Epoxy – Tank White
Tank Construction
Paint by Tnemec
Exterior – 4 Coat System
o Shop Prime – 3.0 mils Series
94 Zinc Rich Polyurethane
o Stripe Coat – 3.0 mils Series
94 – For all Seams and
Abraded Areas
o Finish Coat – 3 Separate
Coats
• 3.0 mils Series N69 Hi-Build
Epoxy
• 2.0 mils Series 73 Endura Shield
(Polyurethane Enamel)
• 2.5 mils Series 700 Hydroflon
Tank Construction
Standby Generator for SCADA
Electrical and SCADA Equipment
Discharge Headwall Structure
Altitude Valve
Tank ConstructionTank Components
Telecommunication Vendors
ATMC/AT&T
Verizon
Town
Communication
Antenna
SCADA Antenna
Tank Construction
Verizon ATMC/AT&T
Telecommunications
Cabling in Tank
Cabling Continues Through
Access Tube
Tank Construction
07 Tank Demolition
Protect
Telecommunications
Structures
Protect Brand New
Tank
Loading of Steel
Components
Tank Demolition
No Complaints or Damage
During Demolition
Three Days from Start to
Finish
Tank Demolition
Valve Vault
Other Structures
Tank Demolition
08 Construction Costs
Original Budget - $1,400,000
As Bid Without Demolition - $1,574,618
After Negotiations with Demolition -
$1,498,600
Final Cost after Change Orders -
$1,475,038.75
Approximately $35,000 Paid by
Telecommunications Vendors
Construction Costs
