UPDATE LOG FOR TECHNICAL PROVISIONS DIVISION 17 Date Item(s) Changed Page # 1/1/09 TECHNICAL PROVISIONS DIVISION 17 WELDED STEEL RESERVOIR

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1 UPDATE LOG FOR TECHNICAL PROVISIONS DIVISION 17 Date Item(s) Changed Page # 1/1/09 TECHNICAL PROVISIONS DIVISION 17 WELDED STEEL RESERVOIR 17.1 Reservoir b. Applicable Standard Specifications. All work shall be in conformance with AWWA D , as latest revised, the AWWA Standard for Welded Steel Tanks for Water Storage, and all referenced standards Change Legend: Added Strike out

2 DIVISION 17 WELDED STEEL RESERVOIR 17.1 Reservoir a. General. The work to be included within this section consists of the furnishing of all materials, tools, equipment, and the necessary labor for fabrication, delivery, testing, erection, assembly, and testing of the steel reservoir of the size and capacity specified below, complete with all appurtenances and fixtures, as shown on the plans and specified herein. b. Applicable Standard Specifications. All work shall be in conformance with AWWA D100-05, as latest revised, the AWWA Standard for Welded Steel Tanks for Water Storage, and all referenced standards. c. Reservoir Data. The name, capacity, diameter, and shell height of the reservoir is as shown on the plans. d. Submittal Data. The Contractor shall submit for approval prior to fabrication, six (6) copies of complete shop drawings showing the principal dimensions, thickness of plates, all structural members and connections, details for all welded joints, appurtenance details, the schedule for completion of the tank construction, mill test reports, and all fabrication and erection drawings. The Contractor shall also submit all design calculations, certified by a registered professional civil engineer licensed in the State of California and experienced with steel reservoir design. The Contractor shall submit both an adopted Injury and Illness Prevention Program and Confined Space Entry Program for the District s review. The Contractor shall submit to the Owner, prior to project completion, a complete certified welding inspection report, and a certificate of compliance if Section 14 of AWWA D is used. e. Foundation. The foundation shall consist of a concrete ringwall and asphalt concrete pavement cushion, all as shown on the plan and as hereinafter specified. The asphalt concrete pavement cushion shall consist of two layers. The bottom course shall consist of six (6) inches of Class II Base and the upper layer shall consist of two and one-half (2½) inches of asphalt concrete pavement, all clean and free of corrosive elements. The allowable soil bearing value for the reservoir is as shown on the plans. All concrete work shall be constructed in accordance with ACI 301. The entire foundation retaining wall should be level with 1 /8-inch in any 30-foot arc and no two points on top of the wall shall differ in elevation by more than ¼-inch. The 17-1

3 expansion joint material used between the concrete ringwall and the tank shall be ½- inch cane-fiber joint filler, meeting the requirements of ASTM D1751. f. Materials. All materials and piping shall conform to the requirements of Section 2 of AWWA D The use of copper-bearing steel is not allowed. g. Design. The design of the reservoir shall be in accordance with Section 3 of AWWA D The minimum design wind velocity shall be 100 mph. The minimum thickness for all materials shall be in accordance with Section 3.10 of AWWA D All pipe columns shall be seal welded. Zero corrosion allowance shall be provided for all items of the reservoir. h. Seismic Design. The seismic design of the reservoir shall be in accordance with Section 13 of AWWA D The use of Section 14 of AWWA D is allowed for the seismic design of the reservoir. The seismic design for the reservoir shall include vertical acceleration and seismic design of the roof. The use factor, I, shall be The amount of freeboard, used for seismic design, is as shown on the plans. i. Roof. The tank rafters shall be provided with adequate bracing to prevent bowing and twisting. The roof shall be as shown on the plans. j. Reservoir Accessories. Except as stipulated herein, reservoir accessories shall be as specified in Section 7 of AWWA D100-96, and each reservoir shall have the following accessories: 1. One inside ladder with safety climb device: See plans. 2. One outside ladder with safety climb device and locking ladder door (Field determined by RCWD Engineer) 3. Two 24-inch diameter shell manholes (hinged and bolted): See plans. 4. One 30-inch x 42-inch roof hatch (hinged and hasped): See plans. 5. Single-flanged shell nozzle: See plans. 6. One 48-inch roof vent provided at apex of roof with a pressure-vacuum screened vent: See plans. 7. Four 8-inch roof vents, distributed on roof: See plans. 8. One target type, full board, water depth indicator (Varec 6700): See plans (Field determined by RCWD Engineer). 17-2

4 9. One drain, size indicated on plans. 10. One overflow drain with weir structure, size and details indicated on plans. 11. Inlet/outlet piping: See plans. 12. Two 1-inch threaded couplings and corpstops: See plans. 13. Two 2-inch threaded couplings and corpstops: See plans. 14. Completed nameplate in accordance with Section 14 of AWWA D100-96, regardless if the reservoir is designed and constructed in accordance with the requirements of Section 14 of AWWA D Testing of Welds During erection of the reservoir, but prior to painting, selected weld areas shall be x-rayed in accordance with AWWA D The Contractor shall include in his bid all costs for the welding inspections and the Contractor shall pay all costs for any re-testing required by faulty welds. The Owner shall not be limited as to the location and the number of tests required by the AWWA Specifications. All vertical welds will be 100 percent tested and circumferential welds spot tested. Contractor shall pay all costs for testing of vertical welds. The Contractor shall submit to the Owner, a complete certified welding inspection report, including weld joint records, radiographs and inspection reports. If the reservoir is designed and constructed in accordance with Section 14 of the AWWA Specifications, the Contractor shall provide a certified welding inspector at no additional cost to the Owner Testing of Floor Welds Upon completion of welding of the tank bottom, the bottom of the tank shall be vacuum-tested with a vacuum box and soap solution or other approved method Inspection and Testing Independent mill or shop inspection is not required by the Owner. The Contractor shall submit complete mill test reports to the Owner prior to fabrication Shell Tolerances Shell tolerances shall be in accordance with Section of AWWA D

5 17.6 Coating of Steel Reservoir See Division 9 "Welded Steel Water Storage Reservoir Coating Specifications." The reservoir may be coated prior to leak-testing the reservoir Safety Requirements Contractor shall abide by all State and Federal safety requirements. Special attention shall be given to California Code of Regulations, Title 8, Division 1, Chapter 4, Subchapter 7 General Industry Safety Orders, Article 108; specifically, Sections concerning work in confined spaces. 17-4