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§ 11.05.020.020 WATER MAINS; DESIGN CONSIDERATIONS.
   (A)   Hydraulic analysis. The design of all water mains shall be based on a hydraulic analysis considering flow demands and pressure requirements.
      (1)   The main must be designed to maintain a minimum normal working pressure of 35 psi and maintain an absolute minimum pressure of 20 psi under all flow conditions.
      (2)   Maximum normal working pressures should not exceed 110 psi.
   (B)   Fire flows.
      (1)   All mains shall be designed to provide adequate fire flows, unless specifically waived by the PWD.
      (2)   The minimum required fire flow shall be 1500 gpm for residential housing or determined by the City Fire Chief at a minimum of 20 pounds per square inch residual pressure at the hydrant during flow in order to meet adopted codes.
   (C)   Diameter. All water main piping shall be at least eight inches in diameter, unless otherwise authorized by the PWD.
      (1)   Larger diameters will be required in order to maintain the minimum pressure requirements of Montana Circular DEQ-1 Standards for Water Works.
      (2)    The city also may require over sizing of mains to meet overall system requirement.
   (D)   Materials.
      (1)   Piping.
         (a)   All water main piping material shall be AWWA C900, 235 psi (DR 18), unless specifically authorized by the City Public Works Department.
         (b)   Water mains larger than 12 inches will meet AWWA C905 pipe requirements.
      (2)   Acrylonitrile butadiene (NBR). Acrylonitrile butadiene (NBR) gaskets will be required for water main installations in areas of known or suspected hydrocarbon contamination.
      (3)   Fittings.
         (a)   All water main fittings, including tees, crosses, caps, plugs, reducers and elbows equal to or greater than 11-1/4° shall use mechanical joint restraints.
         (b)   All mechanical joint restraints shall be “Megalug,” “Uniflange” or approved equal. Joint restraint use shall be in addition to meeting thrust block requirements in accordance with MPWSS.
   (E)   Installation.
      (1)   Existing valve operation.
         (a)   In order to isolate sections of the existing water system to allow for new construction, it will be necessary to operate existing system valves.
         (b)   The PWD must operate existing valves and notification and scheduling, thereof must be coordinated with the PWD.
      (2)   Cover. The minimum cover for all water mains from top of pipe to final finished grade shall be six and one-half feet.
      (3)   Encasement.
         (a)   All water main piping, fittings, valves and the like (excluding PVC pipe) shall be encased in polyethylene wrap with a minimum thickness of eight mils.
         (b)   All encasement shall be in accordance with AWWA C105 standards.
      (4)   Electrical thawing.
         (a)   Conductive brass wedges shall be installed at all joints to provide for electrical thawing.
         (b)   Electrical continuity shall be provided at all flexible, dresser-type couplings.
      (5)   Tracer.
         (a)   Ten-gauge copper coated tracer wire shall be installed along the top of the new PVC water main and shall be attached to all valve box risers.
         (b)   Six-inch wide detectable tape marked “WATER” shall be installed two feet below finished grade along the alignment of the new main and attached to all valve box risers.
      (6)   Cathodic protection. Cathodic protection is required for all water main valves, fire hydrants and fittings.
      (7)   Open trenches. Trenches for the installation of water mains shall be properly backfilled as quickly as possible, but no more than 72 hours after initial excavation.
      (8)   Protection of mains.
         (a)   When working near and/or exposing existing city water mains and service lines, workers shall utilize hand-digging within two inches of mains in order to avoid damage to those pipes.
         (b)   If damage occurs, costs incurred by the city can be imposed.
   (F)   Extension.
      (1)   (a)   Any extension of an existing city water main must be extended through the entire frontage length of the property to be served.
         (b)   Main extensions shall include all valves, pipe sizes, hydrants and appurtenances deemed necessary by the city.
      (2)   Public mains must be connected, extended or looped, in addition to the proposed extension to provide an adequate and functional water supply, and provide for future extensions to adjacent properties.
   (G)   Sewer line crossings.
      (1)   Crossings. A minimum of 18" vertical separation is required when a water main or service connection crosses above or below a sanitary sewer, measured outside to outside of pipe.
         (a)   Please refer to MPWSS for further information on sewer line crossings.
         (b)   Less than 18" vertical separation may be allowed when a gravity sewer at the crossing is made from a single 20' length of AWWA pressure pipe and the crossing is approximately 90°.
            1.   Specific authorization from the Montana Department of Environmental Quality and the PWD is required for a vertical separation of less than ten feet.
            2.   No exception of the minimum 18" vertical separation requirement is permitted when the sewage pipe is a force main.
      (2)   Parallel. A minimum of ten feet horizontal separation is required when a water main and sanitary sewer are installed parallel.
   (H)   Tapping city water.
      (1)   The PWD shall tap all water mains for services up to one inch in size.
         (a)   Preparations for exposing the water main and preparing the water main for tapping, as well as scheduling for the PWD to make the tap are all responsibilities of the water main installer.
         (b)   The City PWD can be contacted at 406-846-2238, ext. 300. All taps require at least 48-hour notice and if a tap requires a main shutdown, 72-hour notice is required, and the contractor is required to notify the affected water users.
      (2)   Any person desiring to make connection to the city’s water or sewer mains must make application in writing and pay for the cost of tapping and any associated system development fees set by the city.
         (a)   All taps shall be made using a Mueller or Ford style FS303 stainless steel saddle for AWWA C900, DR-14 Class 200 PVC pipe.
         (b)   Taps of sizes three-fourths inch to one inch on water mains require the city to do a direct tap and provide a properly sized corporation valve.
         (c)   Special provisions apply for three-fourths inch and one inch taps on four-inch mains. For integrity of the main, these taps require the use of a properly sized tapping saddle, which is required to be purchased and supplied by the plumbing contractor.
      (3)   (a)   Taps for sizes one and one-half inch and two inch on all sizes and types of mains require a properly sized tapping saddle and corporation valve purchased and supplied by the plumbing contractor.
         (b)   Bronze or stainless-steel double strap or wide band tapping saddles are required on service lines up to two inches in diameter.
      (4)   (a)   Taps of larger than one inch must be performed by a licensed, qualified contractor and require a tapping saddle, tapping valve and a valve box to be purchased and supplied by the plumbing contractor.
         (b)   All taps four inches and larger must be air tested prior to tapping.
      (5)   On all taps that require a saddle, the plumbing contractor must provide and install the saddle.
   (I)   Valves.
      (1)   Valves shall be installed in the distribution system at sufficient intervals to facilitate system repair and maintenance as determined by the Public Works Department, but in no case shall there be fewer than one valve every 600 feet.
         (a)   Generally, there shall be two valves on each tee and three valves on each cross.
         (b)   All gate valves shall conform to AWWA C515 standards and shall open clockwise.
         (c)   All butterfly valves shall conform to AWWA C504 standards and shall open clockwise.
      (2)   All tapping valves shall open counterclockwise.
      (3)   (a)   All water valve boxes shall have a concrete collar installed after paving and final grade adjustment.
         (b)   All water valve boxes shall be aligned to allow a four-inch diameter PVC pipe to be inserted in the valve box and centered over the valve nut.
      (4)   All water valve boxes will not be extended more than 50% of the total adjusting range.
   (J)   Fire hydrants.
      (1)   Unless otherwise approved by the Fire Chief, the hydrants shall be spaced no further apart than one standard city block, which is approximately 500 feet.
         (a)   The Fire Chief reserves the right to require additional fire hydrants if the demand of the structure(s) requires more flow than the minimum spacing provides.
         (b)   The placement of all hydrants shall be subject to approval of the City Fire Chief and the PWD.
      (2)   (a)   Fire hydrants shall be 250 psi, five and one-fourth inch, three-way, “Mueller Super Centurion 250,” or approved equal, conforming to AWWA C502 standards.
         (b)   All hydrants shall be painted red above the ground line.
      (3)   (a)   All hydrants shall be equipped with a #4 pentagon (one and one-fourth inch) operating stem nut and shall open in a clockwise direction.
         (b)   The direction of opening shall be indicated by a permanent arrow on the hydrant top.
      (4)   All hydrants shall be designed for final grade of hydrant safety flanges set at one and one-half to three inches above finished grade.
         (a)   Minimum cover depth on the hydrant lead shall be six and one-half feet with a maximum of eight and one-half feet.
         (b)   All hydrants shall have a solid one-piece operating stem; the use of a hydrant extension will only be allowed with prior approval of the PWD and no other option exists.
         (c)   Pipe deflection on hydrant leads shall be minimal and shall not result in finished hydrant more than 1° out of plumb.
         (d)   The hydrant auxiliary valve shall be located in the street pavement or boulevard with a standard water valve and concrete collar.
         (e)   No valves or collars shall be located within the curb and gutter.
   (K)   Water vaults. All underground vaults and manholes associated with the city’s water system shall be constructed of pre-cast concrete sections meeting ASTM C478 or C858.
      (1)   Vault manhole covers shall have the word “water” cast into the top surface.
      (2)   All water vault manhole frames shall have a concrete collar patch poured after paving and final grade adjustment.
(Prior Code, § 11.05.010.020) (Ord. 2019-9, passed 9-3-2019; Ord. 2021-15, passed 12-20-2021)
§ 11.05.020.030 WATER SERVICE LINES.
   (A)   Materials.
      (1)   (a)   All service lines shall be a minimum of three-fourths inch in diameter. All water service lines smaller than four inches diameter shall consist of Type K copper pipe meeting ASTM B88-62 from the main to the curb box.
         (b)   Poly pipe or PVC pipe may be considered on a case-by-case basis in corrosive soil with approval from the Public Works Department.
      (2)   All water service lines four inches diameter and larger shall consist of ductile iron pipe meeting AWWA C151, American National Standard for ductile iron pipe.
         (a)   Stainless steel inserts are required for all compression-type fittings.
         (b)   In accordance with Sections 1417(a) and (b) of the Safe Drinking Water Act amendments of 1986 (Public Law No. 99-339), being 42 U.S.C. §§ 300f et seq., the use of solders and flux containing more than 0.2% lead and pipes and fittings containing more than 8% lead is prohibited in the installation and repair of residential or non-residential plumbing connected to a public water supply system.
   (B)   Installation.
      (1)   All water service lines must be so arranged that the supply to each separate house premises or buildings may be controlled by a separate shut-off valve and curb box placed within the right-of-way near the property to be served.
         (a)   One singular, identifiable entity will be responsible for all the water used through each service.
         (b)   All water service line connections to the water main must be made by a licensed plumber.
      (2)   All individual condominiums and separate buildings, including manufactured homes, must be served by individual service lines from the main. In the cases where individual service lines are not feasible, one service will be allowed with only one master meter that is the responsibility of the condominium associations or one individual for payment.
         (a)   Multiple meters that are read and billed by the city will not be allowed on a single service.
         (b)   In cases where the street is less than ten years old with a single service to the condominium lot, individual meters may be allowed with manifold and a master shut-off valve, along with individual shut-off valves located within the city right-of-way.
      (3)   (a)   At all locations where water service lines are installed beneath new curb, the face of the curb shall be stamped with a “W” in lettering at least three inches tall, for marking the water service location.
         (b)   “Tunneling” under existing curbs, curb and gutter, and the like is prohibited.
      (4)   (a)   All services must be connected to a city main. Service lines may not be connected to fire hydrant leads.
         (b)   A tracer wire must be installed and tested for all poly pipe and PVC services.
   (C)   Curb stops and boxes.
      (1)   Curb stops. All curb stops shall have a bronze plug, tee head key with either a Minneapolis top thread or standard no thread, with a copper flare nut on both connections.
      (2)   Curb boxes. All curb boxes shall be extension-type having a minimum box length, fully retracted, of six feet.
         (a)   All curb boxes shall be Mueller or Ford or equal as approved by the Public Works Department.
         (b)   All curb boxes shall have screw-on or other type lid, which can be attached to the top of the riser.
         (c)   All curb boxes shall be within 1° of plumb and centered directly over the corporation stop nut.
         (d)   A one-inch rigid pipe must be able to pass through the curb box and over the operating nut.
         (e)   The curb box will be part of the final inspection, by the PWD, for building permit or final approval of infrastructure construction.
   (D)   Service line meters.
      (1)   (a)   Water meters, including meter remote read hardware, will be purchased by the property owner and will be installed by a licensed plumber.
         (b)   Meters will be Neptune T-10. Remote readout will be placed on the outside of the building at a location that is easily accessed by city personnel.
      (2)   (a)   All meters must have valves upstream and downstream of the meter in order to isolate the meter for servicing.
         (b)   Meters and remote read hardware, are the property of the city.
      (3)   All meters must be installed in a horizontal line at a minimum of 18 inches and a maximum of four feet from the floor, and a minimum of six inches from any wall.
         (a)   The meter must also be located close to a floor drain.
         (b)   All meters shall be located away from any electrical devices/equipment.
      (4)   All meters larger than two inches shall be either turbine or compound meters and shall be installed in accordance with the manufacturer’s recommendations, including a strainer and bypass with locking type valve.
   (E)   Backflow prevention.
      (1)   BACKFLOW is defined as the undesirable reversal of water flow or the reversal of water flow containing other liquids, gases or other substances from a connected source that flows into the distribution pipes of the public water supply.
      (2)   The city may require, at its discretion, the installation of appropriate backflow protection devices on new or existing service lines when the water user is involved in water use practices that pose a threat to the city’s water system. All existing sources for water that are not part of the city’s water system must be disconnected from the city’s system.
(Prior Code, § 11.05.010.030) (Ord. 2019-9, passed 9-3-2019; Ord. 2021-15, passed 12-20-2021) SANITARY SEWER SYSTEMS
§ 11.05.030.010 GENERAL.
   (A)   Design requirements. Sanitary sewer systems shall be designed, constructed and tested in accordance with the current editions of Circular DEQ-2 - Montana Department of Environmental Quality - Design Standards for Wastewater Facilities and the Montana Public Works Standard Specifications.
   (B)   Design report.
      (1)   All sanitary sewer main extensions shall require the design engineer to submit a written report to the PWD which addresses the design requirements listed herein.
      (2)   The design report shall demonstrate that all sanitary sewer main extensions have adequate capacity to convey wastewater from the anticipated service area and meet the minimum flow velocities and/or flow depth requirements in Chapter 30 of MDEQ Circular-2.
      (3)   The design capacity should be based on 112 gpd per capita for single family residence and an average of 2.1 people per residence.
(Prior Code, § 11.05.030.010) (Ord. 2019-9, passed 9-3-2019; Ord. 2021-15, passed 12-20-2021)
§ 11.05.030.020 SANITARY SEWER MAINS.
   (A)   Design considerations.
      (1)   Slope.
         (a)   Gravity sewer mains shall be installed with slope adequate to maintain flow velocities of at least two feet per second (fps) when depth of flow is at one-third of the sewers main inside diameter, based on Manning’s equation with an “n” value of 0.013.
         (b)   Recommended minimum pipe slopes listed in Section 33.41 of Circular DEQ-2 will be considered adequate.
      (2)   Capacity. Public sanitary sewers and appurtenances shall be designed to accommodate peak hourly flows, including an allowance for infiltration, while flowing no more than half full when no additional connections are possible and a quarter full when future growth is anticipated.
         (a)   The development must upsize the existing mains if the capacity of the sewer main is calculated to be three quarters full.
         (b)   The allowance for infiltration shall be 150 gallons per acre of coverage area per day or otherwise approved by Public Works Department.
      (3)   Diameter. Gravity sewer mains shall have a minimum diameter of eight inches. Increasing the diameter in order to meet the minimum pipe slope requirements will not be allowed.
      (4)   Manholes. Shall be a minimum for 48 inches less the 13 feet of bury for all manholes with bury depth greater than 13 feet a minimum of 60 inches manhole is required.
      (5)   Flow direction. On the infrastructure plans all sewer pipes shall be labeled as to the flow direction.
      (6)   Accessibility.
         (a)   Sewer mains shall be installed in the public right-of way wherever possible.
         (b)   Where mains cannot be installed in the right-of-way, a 20-foot wide exclusive easement with a 14-foot all-weather surface road must be constructed in the easement.
   (B)   Materials.
      (1)   Gravity piping. Gravity sewer main piping shall consist of any of the following materials:
         (a)   PVC meeting ASTM D3034, SDR 35 and 26 (8" to 15");
         (b)   PVC meeting ASTM D679, SDR 26 or ASTM F794 (18" and larger);
         (c)   HDPE meeting ASTM D3350 and ASTM F714;
         (d)   Concrete meeting ASTM C14, C76 or C655; and
         (e)   Other pipe materials specifically approved by the City PWD.
      (2)   Pressure piping. Pressure sewer piping (force mains) shall consist of PVC pressure pipe, ASTM D2241, Class 200 SDR-21, or AWWA C900 DR-18.
      (3)   Manholes.
         (a)   All manholes shall be constructed using pre-cast RCP, unless specifically allowed by the Public Works Department in writing. Structural strength shall withstand H-20 design load.
         (b)   All manholes installed at outfall lines must have PVC liner installed to protect against H2S gas.
      (4)   Manhole ring and cover. Manhole cover shall be stamped “Sewer.” The manhole ring/cover shall have an O-ring type gasket to protect the lid from inflow during storm events.
   (C)   Installation.
      (1)   Alignment and grade. Public sanitary sewers shall be installed with a straight alignment and grade between manholes as required in MPWSS.
      (2)   Location. Municipal wastewater system facilities shall be designed and constructed so that all such facilities are readily accessible for maintenance and repair.
         (a)   In addition, such facilities shall be situated so as to preclude the entrance of surface water into said facilities.
         (b)   All sewer mains shall be centered in the right-of-way or easement to the greatest extent possible.
      (3)   Depth.
         (a)   Sanitary sewers shall be buried to a depth sufficient to prevent freezing and shall have a minimum depth of four feet.
         (b)   Shallower depths may be allowed by the City PWD if suitable pipe insulating provisions are provided.
   (D)   Extension.
      (1)   Any extension of an existing city sanitary sewer main must be extended through the entire frontage length of the property to be served, with a standard manhole located at the terminus of the new sewer main.
      (2)   Sewer main extensions shall include all manholes, clean-outs and appurtenances deemed necessary by the city.
   (E)   Water line crossings.
      (1)   Crossings. A minimum of 18-inch vertical separation is required when a sanitary sewer main crosses above or below a water main, measured outside to outside of pipe.
         (a)   Please refer to MPWSS for further information on water line crossings.
         (b)   Less than an 18-inch vertical separation may be allowed when the gravity sewer at the crossing is made using a single 20-foot length of AWWA pressure pipe and the crossing is approximately 90° and the length of pipe is centered over the crossing.
            1.   Specific authorization from the Montana Department of Environmental Quality and the City PWD is required for a vertical separation of less than 18 inches.
            2.   No exception of the minimum 18-inch vertical separation requirement is permitted when the sewage pipe is a force main.
      (2)   Parallel. A minimum of ten-foot horizontal separation is required when a sanitary sewer main and water main are installed parallel.
(Prior Code, § 11.05.030.020) (Ord. 2019-9, passed 9-3-2019; Ord. 2021-15, passed 12-20-2021)
§ 11.05.030.030 SEWER SERVICE LINES.
   (A)   Materials.
      (1)   Gravity sewer service piping. Gravity sewer service piping shall consist of the following materials for the following situations:
         (a)   PVC meeting ASTM D3034, SDR-35 and 26 or PVC Schedule 40 - solvent weld or SBR gasket joint for normal installations. PVC Schedule 40 or cement lined ductile iron for installation within two feet of a building foundation;
         (b)   PVC Schedule 40 for water main or water service crossing; and
         (c)   PVC Schedule 40 with acrylonitrile butadiene (NBR) gaskets for installations in areas of hydrocarbon contamination.
      (2)   Pressure sewer service piping. Pressure sewer service lines shall consist of PVC pressure pipe, ASTM D2241, Class 200 SDR-21.
   (B)   Installation.
      (1)   (a)   All sanitary sewer service lines must be so arranged that the discharge from each separately-owned house premises or buildings on separate lots is a separate service line that connects to the main.
         (b)   The owner of each house or premises is liable for the charges for the wastewater service provided by the city to that owner’s house or premises.
      (2)   Sewer service lines shall be installed with a minimum of four feet of cover from the top of service pipe to finished grade.
      (3)   (a)   At all locations where sewer service lines are installed beneath new curb, the face of the curb shall be stamped with an “S” in lettering at least three inches tall, for marking the sewer service location.
         (b)   Tunneling of sewer service under curb, curb and gutter, sidewalks and the like is prohibited.
   (C)   Tapping city sewer.
      (1)   Any person desiring to make connection to the city’s water or sewer mains must make application in writing and pay for the cost of tapping in accordance with city policy, resolution or ordinance.
      (2)   (a)   All applications for service connection to the city’s wastewater system must be made at the front counter at city hall.
         (b)   Every such application must be made by the owner of the property to be served or the owner’s authorized agent and must include the nature of wastewater discharged into the system.
   (D)   Metering when not on city water. For new city sewer services which do not use the city water system or whose water consumption or wastewater discharge is not otherwise metered, the Public Works Department shall require the installation of a suitable metering device in order to determine an equitable charge for sewer services.
(Prior Code, § 11.05.030.030) (Ord. 2019-9, passed 9-3-2019; Ord. 2021-15, passed 12-20-2021)
§ 11.05.030.040 LIFT STATION.
   (A)   Capacity. The design capacity for a lift station shall be designed to a reasonable capacity based on similar flows from comparable zoned areas.
      (1)   The designer shall provide a table in the design report for the design capacity for each non-residential lot.
      (2)   Multi-family lots with a four-plex or greater are also considered commercial lots.
      (3)   (a)   During the building review process, a letter from an engineer must be submitted certifying that the sewer capacity is not greater than the original design capacity of the lot.
         (b)   If the capacity for the building is greater, additional capacity may be required.
   (B)   Building. The building shall be constructed of masonry block or similar high durability construction material.
      (1)   The building style must be compatible with the surrounding environment.
      (2)   The developer must install and provide access to the building so maintenance equipment can access the building and wet well.
   (C)   Landscaping. All lift stations must have low water/native vegetation and trees for the landscape screening with an irrigation system
   (D)   Fencing.
      (1)   All lift stations must be fenced with an eight foot high black vinyl coated chain link fence with two-strand barbed wire top.
      (2)   A minimum of two lockable gates must be provided; one for pedestrian access and one double gate that is able to swing 180° for allowing maintenance equipment to access the site.
   (E)   Wet well. Must be lined with a PVC coating or approved equal by the Public Works Department.
   (F)   Piping.
      (1)   (a)   All piping must be stainless steel within the wet well and ductile iron in the building.
         (b)   The pipe must also be configured to accommodate bypass pumping with a blind flanged tee after the last check valve.
      (2)   (a)   All fittings must be located out from under the lift station slab or located within a grated trench.
         (b)   All fittings must be accessible without damaging the building.
   (G)   Valving.
      (1)   All check valves must have external levers.
      (2)   A three-way Dezerik plug valve must be installed at the point the two pumping lines join.
   (H)   Safety.
      (1)   The wet well shall have a safety grate that is easily removable and integral to the hatch.
         (a)   The grate must be rated to at least 1,000 pound of loading.
         (b)   In addition to the hatch with a safety grate, removable handrails must also be supplied.
      (2)   (a)   A compressor and two full-face masks with a minimum 50-foot hoses will be required for a fresh air supply.
         (b)   SCBA will not be acceptable as a fresh air supply.
   (I)   Pumps. The pumps shall be Gorman-Rupp, Paco, Flyght or equal as approved by the PWD.
   (J)   Telemetry.
      (1)   The telemetry must be designed in accordance with the city telemetry design standards.
      (2)   If no standards exist, coordinate with the PWD.
   (K)   Pigging stations. Any lift station with a force main of more than 2,000 feet that does not have an existing flow of 50% of the design capacity, must have pigging stations for cleaning of the force main.
   (L)   Odor control. All vents from the wet well or force main must have a carbon filter.
   (M)   On-site generator. All lift stations must be supplied with an on-site generator.
      (1)   The generator must be a natural gas or diesel fuel unit located in a separate room within the building.
      (2)   An access door big enough to remove the generator for maintenance will be required.
(Prior Code, § 11.05.030.040) (Ord. 2019-9, passed 9-3-2019; Ord. 2021-15, passed 12-20-2021)
STORMWATER MANAGEMENT
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