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Private and Publicly Owned Distribution System Water Main Pipe MaterialsCity of Dubuque City Council Meeting Action Items # 01. Copyrighted November 6, 2023 ITEM TITLE: Private and Publicly Owned Distribution System Water Main Pipe Materials SUMMARY: City Manager recommending City Council approval of the continued use of poly -vinyl chloride (PVC) and ductile iron pipe (D I P) for public drinking water mains privately or publicly owned -and -operated in the City of Dubuque, or as extended, with the intent to be connected to the City of Dubuque's water distribution system; and that the City of Dubuque continue to use the SUDAS Specification and Design Manual for water mains, adopted by City Council resolution 211-23 on July 5, 2023, as a uniform standard for design and installation; and suspend use of the Division 5 of the City of Dubuque SUDAS Supplemental standards as it pertains to Water Main materials specifically until such time as a formal review is conducted. SUGGESTED Suggested Disposition: Receive and File; Approve DISPOSITION: ATTACHMENTS: Description Type MVM Memo City Manager Memo SUDAS Recommendation for Water Main Materials Staff Memo MVM Memo THE CITY OF Dubuque DUB TEE1. All -America City Masterpiece on the Mississippi � pp zoo�•*o 13 zoi720zoi9 TO: The Honorable Mayor and City Council Members FROM: Michael C. Van Milligen, City Manager SUBJECT: Private and Publicly Owned Distribution System Water Main Pipe Materials DATE: November 1, 2023 Water Department Director Christopher Lester is recommending City Council approval of the continued use of poly -vinyl chloride (PVC) and ductile iron pipe (DIP) for public drinking water mains privately or publicly owned -and -operated in the City of Dubuque, or as extended, with the intent to be connected to the City of Dubuque's water distribution system; and that the City of Dubuque continue to use the SUDAS Specification and Design Manual for water mains, adopted by City Council resolution 211-23 on July 5, 2023, as a uniform standard for design and installation; and suspend use of the Division 5 of the City of Dubuque SUDAS Supplemental standards as it pertains to Water Main materials specifically until such time as a formal review is conducted. I concur with the recommendation and respectfully request Mayor and City Council approval. Micliael C. Van Milligen MCVM:sv Attachment cc: Crenna Brumwell, City Attorney Cori Burbach, Assistant City Manager Christopher Lester, Water Department Director Rick Dickinson, Greater Dubuque Development Corporation President & CEO Dave Lyons, Greater Dubuque Development Corporation Strategic Initiatives Consultant THE COF Dubuque DtUB E MI-America6iiy xsniurnrir,+.�. 1IIII®r Masterpiece pp iece on the Mississippi z°°'"Z°i 2-2013 zoi7*2019o�9 TO: Michael C. Van Milligen, City Manager FROM: Christopher Lester, Water Department Director SUBJECT: Private and Publicly Owned Distribution System Water Main Pipe Materials DATE: November 2, 2023 INTRODUCTION The purpose of this memorandum is to recommend the continued use of poly -vinyl chloride (PVC) and ductile iron pipe (DIP) for public drinking water mains privately or publicly owned -and -operated in the City of Dubuque, or as extended, with the intent to be connected to the City of Dubuque's water distribution system; and that the City of Dubuque continue to use the SUDAS Specification and Design Manual for water mains, adopted by City Council resolution 211-23 on July 5, 2023, as a uniform standard for design and installation; and suspend use of the Division 5 of the City of Dubuque SUDAS Supplemental standards as it pertains to Water Main materials specifically until such time as a formal review is conducted. BACKGROUND The city of Dubuque's Water Department carries the responsibility of operating, maintaining, and executing capital projects associated with the city's drinking water distribution system. The city's drinking water infrastructure is comprised of cast iron pipe, ductile iron pipe, poly -vinyl chloride (PVC) pipe, and in five locations, lead water mains. There is an estimated total of 333 miles of public water main and an estimated 60 miles of water main that are privately operated and maintained within the Dubuque service area. DUBUQUE: PUBIC VS.PRIVATE WATER MAINS ■ Public Water Main, Miles ■ Private Water Main, Miles Most of Dubuque's public water mains are cast iron or ductile iron with some small diameter copper and lead water mains serving small cul-de-sacs and dead ends, estimated at 300 miles and approximately 33 miles are PVC in contrast to an estimated 7 miles, or 17%, of private water mains are PVC. The largest ductile iron water main is the 30-inch discharge pipe leaving the Eagle Point Water Treatment Plant; and the largest cast iron water main is thought to be the 24-inch feed line to the West 3rd Street 7.5MG ground storage reservoir. The largest diameter PVC public water main pipe in the system is 16-inch. DUBUQUE: METAL WATER MAINS VS. PVC WATER MAINS ■Cast, Ductile Iron (All Metal) Pipe, Miles ■ PVC Pipe, Miles Since the 1950's, following reduced need for iron ore that were in high demand for the war effort, the use of ductile iron remains the preferred pipe material. PVC pipe, however, has increased since its general use in the US market also since the 1950's, with its use in Dubuque starting more recently, but not at the rate of ductile iron installation. The following discussion is a researched analysis examining water main pipe materials commonly used and approved in the drinking water industry and the information available to best determine the most suitable pipe materials to use in Dubuque, Iowa's drinking water infrastructure. Discussion The first part of the analysis is a review of the current City of Dubuque standards pertaining to accepted water main pipe materials. Currently, these are Ductile Iron Pipe and PVC. Current City of Dubuque Water Main Standards and Specifications The current Water Department Standards as adopted and revised September 12, 2011, by the Iowa Department Natural Resources (DNR) for water main are as follows: Ductile -iron pipe (DIP) shall be USA manufactured and tested in accordance with AWWA Specifications C151. DIP size shall be four -inch (4') through 12- inch, 16-inch, 20-inch and 24-inch, unless otherwise approved by the Water Department. Polyvinyl Chloride Pipe (PVC) by request, may be made be made to the Water Department. The request shall include the results of an IDNR required review of records for any leaking underground storage tank (LUST) site within 1, 000* feet of the proposed water main construction. In areas where PVC pipe use is requested and there is no IDNR information available, the requestor could be required, based on the condition and previous use of the site(s), to provide the Water Department with a Phase One Environmental Study. Upon receipt of the required information, the Water Department will determine if PVC pipe may be substituted for DIP. PVC pipe may be substituted for DIP under certain soil and ground -water conditions, where there is no environmental contamination by petroleum products or any other type of contaminants that might permeate PVC pipe or cause damage to PVC pipe. PVC pipe may not be installed within 1000 feet of property zoned commercial or industrial without prior authorization from the City Manager or the City Manager's designee. PVC pipe may be substituted for ductile iron pipe in residential areas for size 8-inch or 12 inch. Per Iowa DNR, if a LUST site is within 1000* feet, the designer is to contact the Iowa DNR Records Center to obtain the Utility Notification Form and the plume maps for the site. These maps are to be used for determining the area of concern. The water main should be ductile iron pipe (DIP) with nitrile or fluoroelastomer (FKM) gaskets wherever the proposed water main would be in contact with a plume. *NOTE: Since 2021, 1000 ft has been reduced to 500 ft. The current standard requires the use of PVC is by request and review, as a result the primary material for water mains in Dubuque, by Standard, has traditionally been ductile iron, which correlates to the water main data presented in the introduction of this analysis. Standards and Specifications used in Iowa The second part of this analysis is a review of Standards and Specifications of water main pipe materials following a survey of other Iowa communities and the generally adopted SUDAS or Statewide Urban Design and Specification manuals. The Iowa Department of Natural Resources, the entity responsible for granting construction permits as signed and sealed by licensed professional engineers, recognizes the following construction standards: • Statewide Urban Design and Specifications (SUDAS) • Recommended Standards for Water Works (commonly known as the Ten - States Standards) Policies for the Review and Approval of Plans and Specifications for Public Water Supplies, as adopted through 2012, • American Water Works Association (AWWA) Standards as adopted through 2016, and • 567 of the Iowa Administrative Code (IAC) subrules 43.3(7) to 43.3(9). To the extent of any conflict between the Ten States Standards and the American Water Works Association Standards and IAC 567--43.3(7) to 567--43.3(9), the Ten States Standards, IAC 567--43.3(2), and IAC 567--43.3(7) to 43.3(9) shall prevail. Recommended Standards for Water Works (commonly known as the Ten -States Standards) The Ten -States Standards were created from a report of the Water Supply Committee of the Great Lakes --Upper Mississippi River Board of State and Provincial Public Health and Environmental Managers, of which Member States and Province include Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, New York, Ohio, Pennsylvania, Wisconsin, and later the Province of Ontario, Canada. The Standards are reviewed and updated as necessary, and establish a basis of engineering design suitable for the conditions typically and most commonly experienced in and around the Great Lakes region, including heavy industry leading to soil contamination and external pipe corrosion, varying topography leading to varying and somewhat excessive water pressures, and similar weather patterns of extreme heat and cold leading to aggressive freeze/thaw cycles, all of which are key risk factors used to determine the best and most suitable pipe materials. The Ten -States Standards address the selection of pipe materials, stating that special attention shall be given to selecting pipe materials which will protect against both internal and external pipe corrosion. Iowa Code Also at the State level, is Iowa Code 567-43.3(455B) Public water supply system construction. While the code is silent on ductile iron pipe, it specifically addresses the use of PVC in its Standards for Construction, Section 43.3(2)(1) Polyvinyl chloride (PVC) pipe. PVC manufactured in accordance with ASTM D2241, AWWA C900, AWWA C905, ASTM F1483, or AWWA C909 may be used for water main construction. The standard while granting the use of PVC, speaks to the maximum allowable pressure for PVC or polyethylene (PE) pipe shall be determined based on a safety factor of 2.5 and a surge allowance of no less than two feet per second (2 fps). This is important, as Dubuque has multiple pump stations where the discharge pumped pressure can exceed the manufacturer's maximum allowable pressure for PVC pipe, adding an additional risk factor which is used by design engineers when selecting water main pipe materials. SUDAS Since 2005, the Iowa Department of Transportation through Iowa State University (ISU) supported by several Iowa collaborating institutions, counties, and municipalities, created the Iowa Statewide Urban Design and Specifications (SUDAS). According to ISU, the value of the SUDAS Design and Standard Specifications Manuals is found in the uniformity created from design through construction. Both designers and contractors have become familiar with the SUDAS manuals and thus are able to provide cost-efficient services. The SUDAS manuals are set up for statewide use with the intent that the Standard Specifications Manual is written to the contractor. The engineer provides specific requirements through the specifications for the contractor to complete the project. These standard specifications were developed with the involvement of engineers and construction industry representatives from across the state. The SUDAS manuals not only provide a uniform standard for municipalities across Iowa, but they also provide one place where design engineers and contractors can trust will include the design standards of the Recommended Standards for Water Works (commonly known as the Ten -States Standards), cross references to AWWA standards, and adherence to the Iowa Administrative Code. Of note, Ames, Ankeny, Cedar Rapids, West Des Moines, Des Moines, Iowa City, and Marion acknowledge adoption and use of the SUDAS standards. SUDAS and City of Dubuque The city of Dubuque initially adopted SUDAS Specification and Design Manuals in 2014 and added supplemental standards with annual updates as necessary to the specification manual and recently to the design manual reflecting Dubuque specific requirements. Several other Iowa municipalities quickly followed suit including Ames, Ankeny, Cedar Rapids, West Des Moines, Des Moines, Iowa City, and Marion. Under Section 5 of the SUDAS Specifications manual, the standard primarily authorizes the use of two water main pipe materials, ductile iron pipe and PVC. The SUDAS Specification Manual provides for the use of: Polyvinyl Chloride (PVC) Pipe for 4-inch through 24-inch diameter sizes shall have a pipe thickness with a Dimension Ratio (DR) of 18, and by design, sizes over 24-inch in diameter, as specified in the [design engineer] contract documents. Ductile Iron Pipe (DIP) for 4-inch through 24-inch diameter have a wall thickness Class 52 according to AWWA C151, for diameters over 24 inches, designed and specified in the contract documents. DIP shall also be cement -mortar lined in accordance with AWWA C104, and seal coated with an external seal coating according to AWWA C151. The SUDAS Design Manual states the following requirements and considerations when using PVC and DIP: Water main pipe will typically be either polyvinyl chloride (PVC) pipe or ductile iron pipe (DIP); and meet AWWA Standards. Designers should use the Iowa DNR's website to determine if there are any leaking underground storage tanks (LUST) sites within 500 feet of the proposed water main: https://facilitvexplorer.iowadnr..qov/facilityexplorer. Where distribution systems and service connections are installed in areas of known groundwater contaminated by volatile organic compounds (LUST), pipe and joint materials (non -PVC pipe) that do not allow permeation of the volatile organic compounds must be used. The Iowa DNR requires underground storage tank (UST) owners to meet specific design requirements for USTs installed within 1,000 feet of a community water system. The Project Engineer should determine if there is an UST within 1,000 feet of the project area. If so, the Designer should determine the need to design the water mains to prevent future permeation of any volatile organic compounds into the water system. There are various elements to consider, some of which include soil types, groundwater table depth, size of the UST, age of the UST, etc. Consult with manufacturers concerning permeation of the pipe walls, jointing materials, valve seats, etc. Water mains should be adequately protected from corrosive soil environments. Comply with AWWA C105. Complete soil testing or check with the Jurisdictional Engineer to determine if corrosive soils are present within the project area. If so, include polyethylene encasement for ductile iron pipe, valves, and fittings or use of other nonmetallic pipe materials. If nonmetallic materials are used, be sure to provide polyethylene encasement for fittings and valves. In severe instances, cathodic protection may be required. The SUDAS Specification and Design Manuals provide the city, developer, contractor, and design engineer the necessary information to make uniform evaluations and sound engineered decisions when working with PVC and DIP water main pipe materials. REQUEST I respectfully request the continued use of poly -vinyl chloride (PVC) and ductile iron pipe (DIP) for public drinking water mains privately or publicly owned -and -operated in the City of Dubuque, or as extended, with the intent to be connected to the City of Dubuque's water distribution system; and that the City of Dubuque continue to use the SUDAS Specification and Design Manual for water mains, adopted by City Council resolution 211- 23 on July 5, 2023, as a uniform standard for design and installation; and suspend use of the Division 5 of the City of Dubuque SUDAS Supplemental standards as it pertains to Water Main materials specifically until such time as a formal review is conducted. cc: Gus Psihoyos, City Engineer Wally Wernimont, Director of Planning Services Arielle Swift, Public Works Director Bob Schiesl, Assistant City Engineer Max O'Brien, Civil Engineer II Nate Kieffer, PE/PLS Land Surveyor Todd Irwin, Engineering Tech Charlie Gau, Engineering Assistant Darrin Homb, Water Distribution Supervisor File