This document provides an overview of best practices for installing and maintaining water distribution systems, including water mains, service lines, valves, hydrants, and other components. Key points covered include recommended pipe materials and sizes, minimum burial depths, separation from sewers, procedures for wet and dry taps, and installation details for valves, hydrants, and service connections. Operational considerations are also discussed, such as flushing, valve operation, and hydrant usage. Reference materials including AWWA standards are listed for additional guidance.

1. Water Main / Extensions Service Line Installation Valves & Hydrants Fereshteh Doost, P.E. Fuss & O’Neill, Inc. (860)-646-2469 Ext. 5295 June 2010

2. Products Pipe, Fitting, Valves, etc. – Latest edition of AWWA Standard. All pipe, paints, linings, coating, for potable water must meet NSF/ANSI Standard 61 Criteria. Material shall stand internal and external pressure and force while in service. Material shall be protected against internal and external corrosion. Non metallic buried pipe shall include a tracer wire, detection tape.

3. Pipe Materials Material Size Length Gray Cast Iron Pipe (CIP) 3” - 54” 12’, 16’, 18’, 20’ Ductile Iron Pipe (DIP) 4” - 64” 18’, 20’ Steel Pipe (SP) 4” - 96” 40’ Asbestos Cement Pipe (ACP)* 4” - 42” 10’ - 13’ Reinforced Concrete Pipe (RCP) 60”- 144” 8’ - 24’ Plastic Pipe PVC C-900 4” - 12” 20’ - 40’ *No longer used.

4. Separation & Layout 10 feet horizontally from sewer, edge to edge 18” vertically above sewer, crown to invert Loop Water Main Avoid Dead-End if possible Routinely Flush Dead-End

5. Water Main Installation In accordance with AWWA Standard. All materials shall be kept clean. Plug open ends. 4.5’ to 5’ minimum cover (prevent freezing) Insulation for pipes passing above or below culvert and bridge. Shut off valve at both sides of bridge. Thrust block and/or restrained joints, to prevent joint separation (bends, tee, hyd. Reducer, caps)

6. Restrained Joints

7. Concrete Thrust Blocks

8. Water Main Extension Need to understand existing configuration Materials of existing main is very important Need to be careful not to contaminate existing main (HPC testing is very helpful) Can be done under 2 circumstance Dry tap Wet tap

9. Dry Tap Need to be able to isolate the portion of main to be extended Make sure valves available to isolate the area work Some leakage of valves is okay, but can hinder progress Be cautious when dealing with asbestos cement or transite Thrust restraints should be designed accordingly

10. Dry Tap (cont.) If connection is in form of a tee, make sure tee assembly is complete prior to cutting main Notify customers of the potential interruption in service Should begin any extension with a new gate or butterfly valve

11. Wet Tap Typically a tapping sleeve & valve is used Disinfect sleeve and valve interiors with bleach prior to installation Sleeve is bolted onto existing main Existing main is then live tapped Gate valve is closed to allow removal of the tapping machine at completion of tap Outside diameter of existing main is critical Thrust restraint should be designed accordingly

12. Wet Tap Example

13. Water Services For this section we will deal with domestic services under normal pressures (up to 100 lbs.) AWWA Standard C800 outlines water services Fire services are an issue in commercial areas and will not be discussed in detail

14. Water Service Components There are 4 basic components to most services Corporation Stop Service Pipe Curb Stop Water Meter

15. Water Service Installation Details

16. Typical Service Connection

17. Service Valves

18. Corporation Stop Provide a means of shutting off water while installing service Typically made of bronze Typically not provided with service box Usually a ball valve type Always attached directly to the water main Corporation is usually mounted in the 2:00 position (between 1:00 – 2:00 position)

19. Corporation Stop (cont.) Two ways to attach stop to water main Direct tap Involves tapping the corporation stop directly to the main Usually this applies to small stops tapped to metal pipe Metallic pipe is usually required on main line Not used for high pressure applications Saddle tap For plastic pipe, corporation is often attached using a pipe saddle Typically used with larger (2” and larger) taps The saddle provide structural backing for the tap Corporation is then attached to the saddle High pressure applications

20. Service Saddle

21. Service Pipe Most common material is copper (type K) Plastic, steel, and iron pipe can be used Lead had been used, but should be removed when found Pipe extends from corporation to curb stop, then into home to meter

22. Service Pipe (cont.) Typical sizes are between 5/8-inch to 2-inch in diameter for a domestic service Services can be as 2-inches and larger for fire services It is not uncommon for multiple homes to be fed from a single service Each service should be equipped with curb stop to allow shut-off without interrupting other customers

23. Curb Stop Provides a means of shutting off water after completion of water service construction Typically located at the property line Usually defines break in ownership Utility usually owns from main to curb stop Private owner owns from the curb stop into the home

24. Curb Stop (cont.) Typically made of bronze Provided with service box Operating key is usually between 1 to 2-inch depending on the service size Usually a ball valve type Direction of opening valve should be utility standard (can be provided in either direction)

25. Typical Curb Stop

26. Water Meters The final component of the service is the meter Provides the utility a means of charging consumer for water used There are many types of meters available Meters can be remotely read Meter readings can also be transmitted directly to billing office

27. Appurtenances Shut-off valves – determined by public water system (PWS) Air-release valve at high point to release and remove air. Blow-offs at low point where sediment accumulates. Flushing device location by (PWS) - Flushing device shall not be directly connected to any sewer. - Flushing device shall have minimum velocity of 2.5 fps

28. Valves The most common valve in a distribution system is a gate valve (AWWA C500, C509, or C515) Gate valves are used to isolate portions of the system For 16-inch and larger diameter pipes, butterfly valves are often used (AWWA C504) Usually 1,000 foot spacing is used

29. Gate Valve

30. Gate Valves The direction to open the valve is critical Valve body can be either ductile or cast iron Valves are usually epoxy coated (AWWA C550) Typically provide a “cluster” at each intersection The two basic types of gate valves are Resilient wedge (AWWA C509) Double disk (AWWA C500)

31. Gate Valves (cont.) Resilient Wedge Stops flow using a rubber encapsulated iron wedge Used for diameters less than 14-inches For >14-inch double disks can be used although RW can still be used Bypass typically used on gate valves > 16-inches Manufacturer recommends not testing against a resilient wedge valve When newly installed, operate (open and close) several times to insure proper sealing

32. Resilient Wedge Gate Valve Section

33. Gate Valves (cont.) Double Disk Stops flow using a double metal disk mechanism Its use is being phased out Use today is typically limited to diameters over 14-inch Bypass typically required on installations > 16-inches

34. Gate Valves (cont.) Gate valves are used for smaller pipe Less expensive compared to butterfly valves for small pipe (<= 12-inch) Many turns to open (3 x diameter + 3): for 8-inch it would take (3 x 8 + 3 =) 27 turns to open Mechanical joints need to be restrained Pressure force on large diameter gates make opening difficult Gates are accessed using a gate box Wrenches for opening gates should be standard for a given utility

35. Gate Valve Section View

36. Butterfly Valves More expensive compared to gate valves for smaller pipe, but more economical for larger pipe – 16-inch or greater Cracking valve equalizes pressure; assists in opening ¼ turn will open or close the valve Mechanical joints are preferred Buried valve is accessed using gate box Bypass valves typically not required

37. Typical Butterfly Valve

38. Hydrants AWWA Standard C502 & C503 outlines hydrants There are 2 basic types: wet or dry barrel Hydrant assembly is composed of the following Anchor tee Branch piping (6-inch diameter) Gate valve Hydrant Thrust restraint is a major concern for hydrants All joints from tee to hydrant should be restrained

39. Hydrants (cont.) AWWA recommends spacing hydrants <500 feet Direction of opening the hydrant should match gate opening direction Hydrants are usually located at the back of sidewalk Do not locate hydrants too close to structures, poles, etc. (can’t get to hydrant during fire) Try to place at property line to prevent interference with future drives, walkways.

40. Typical Hydrant Section View

41. Typical Hydrant Installation

42. Hydrant Operation Operator needs to understand hydrant operation In New England, hydrants are dry barrel type Dry barrel hydrants are often equipped with drain ports to drain barrel Drain ports are not allowed in some jurisdictions (Maine) Do not throttle with hydrant, use gate valve Not fully closing hydrant can cause scouring of base through drain ports Closing hydrant too quickly can cause water hammer and possible break Be careful of final couple of turns

43. Hydrant at Dead End

44. Hydrant Operation (cont.) Operator’s understanding (cont.) NEVER THROTTLE A HYDRANT WITH THE OPERATING NUT If hydrant needs to be throttled, use gate valve When operating always either fully open or close the hydrant Never stand in front of hydrant cap when pressurizing; stand behind hydrant in case cap ‘blows” off

45. Hydrants (cont.) Air release valves should be installed at high points to bleed entrained air. Hydrants have been used in lieu of air release valves with mixed results Hydrants located at low points can be used to flush deposited materials Smaller diameter flushing hydrants also available

46. Reference Materials AWWA Standards NFPA Water Distribution System Operation and Maintenance, fourth edition State Guidelines and Policies for Public Water Systems Ten State Standards

47. Questions?