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H1. Public Hearing - Amend Design StandardsCity of Kalispell Post Office Box 1997 - Kalispell, MT 59903 Telephone: (406) 758-7701 Fax: (406) 758-7758 To: Doug Russell, City Manager From: Susie Turner, P.E., Public Works Director Re: Public Hearing for the Proposed Amendment of the Kalispell Design and Construction Standards Meeting Date: December 5, 2016 BACKGROUND: In the 2015 City Standards for Design and Construction -Special Provision Section for sanitary sewer there was a Montana Pubic Works Standard Specifications (MPWSS) reference error that requires an amendment. Inadvertently, sections referencing sewer testing requirements and measurement and payment from the MPWSS for sewer main installations were deleted. In order to correct the unintentional deletion of required sewer main testing, an amendment to the 2015 City's Standards removing the following two lines of text from Special Provision 02730 — Sanitary Sewer Collection System section is required. Delete Subsection 3.4.C, D, & E of the Standard in their entirety. Delete Part 4 in its entirety. As part of the consideration for the standards amendment, notification and public hearing processes are applicable. As such, the requirement for a public hearing prior to Council taking action for the proposed amendment is scheduled for the December 5, 2016 Council Meeting. The Council would then take action on the proposed amendment at the December 19, 2016 Council meeting. The proposed amendment was advertised via local newspaper, social media and circulated to the local engineering, construction and development community requesting input and comments on the proposed amendment. Thus far, the City has not received comments from the public. ATTACHMENTS: 1) 2015 City of Kalispell Standards for Design and Construction document can be found on the City's website using the following link: Httr)://www.kalisr)ell.com/public works/documents/StandardsforDesianandConstruction-April2015- Final.pdf 2) Montana Public Works Standard Specifications (MPWSS) Section 02730 -Subsection 3.4.C, D,&E and Part 4 Montana Public Works Standard Specifications (MPWSS) Section 02730-Sanitary Sewer Collection System Subsection 3.4.C, D, & E, and Part 4 e. Construct manholes meeting ASTM C478_ and the rejection criteria stated therein. f Keep manhole construction within one manhole distant behind sewer pipeline construction. Install adjusting rings on each manhole to bring the manhole tap ele�,-atiam to snatch the existing or specified ground ele-,•ations_ Use manhole rings with a 2-inch fll iflirmlm (5 cm) and 12-inch (30 cat) maximum height_ Furnish adjusting rings reinforced with the same percentage of steel as the riser and tap. A- Construct service Lines meeting Standard Ira,.ving 02730-2_ Install the sen�ke line to the property line. Plug the end of the seMce Line with a stopper and gasket, using a gasloet of the same type used for pipe jointing. Donor grout the plugs- B. Mask the sanitary sewer and storm drain service Line ends at the property line using a steel fence past 5 feet (1.5 m) long; buried at least 2 feet (0.6 nib_ Place a 2" X 2" (5cm X 5 cm) mood marker extending from the pipe invert to ground line. Wire the 2" X 2" (5cm X 5 cm) marker to the steel fence post. )A%ere applicable_ mark the concrete curb to identify the service locations. Paint sanitary sewer service markers green and storm drain sen-ice markers gray. . A_ Maloe all tests after backfill is completed, but before any surface restoration or street surfacing_ Be responsible for finding and repairing all breaks and leaks revealed by the tests. Additionally, perform all tests in the presence of the Engineer. resident inspector, or the Owners other designated representative. B. Light Test (Visual) After the trench has been backfilled and compacted as specified in Sectio U 02221, perform a light test between manholes to check alignment and grade for pipe displacement. Excluding cun-ed alignments shown on the plans, the completed pipeline is to permit a true circle of light to be risible from one manhole to the next_ If alignment or grade is not that specified and displacement of pipe is found_ remedy all defects. C. Leakage Test New seiner line will not be fmally accepted until leakage tests are made assuring the Engineer that pipe laying and jointing are satisfactory. Sectian 02730 — e Edi& m SANrrARY SE -= COLLET O'q SYSTEM Pare 9 of 15 D- Water Test Where groundwater is at least 2 feet (D.6 m) above the seiner ]sue_ snake tests by sealing oft` the section of lines between manholes and measuring the actual floes; by collecting or pumping the discharge into b air'els or other approved methods. Continue tests at a minimum of 4 hours for each section tested. Allow time to soak lines and manholes iu advance of performing tests. 176'hen graundwater is nut 2 feet (0.6 m) abova the pipe, test as follows: On flat slopes where the depth over the centerhae of the pipe m the lower manhole of the section being tested will be not more than 10 feet (3 m), fill the upper manhole to 2 feet (0.6 m) over the tap of the pipe or 2 feet (D.d m) above the groundwater elevaticm (whichever is higher), and black the lower manhole_ When the above conditions cannot be met, the Engineer may order testing the line in sections between manholes - Measure the leakage by checking the water level drop in the manhole mw a 4 hour- period. The allowable infiltration or exMtration_ including manholes_ cannot exceed 200 gallons per day per mile of seiner p-er inch of pipe diameter (195 liners per day per kilometer of sewer per centimeter of pipe diameter) - This does not exclude obvious and concentrated leaks and physical defects, such as open joints, pinched gaskets, cracked barrels or bells, etc. Make repairs on concentrated leaks, and as required to reduce infilfratirm or exfiltration leakage below the specified rate. E. }fir Test (Alternative) As an alternate method to water testing, the Contractor may utilize lam; pressure air to test the sewer imp inQ. Use the test procedure described below-. Plug bath ends of the pipe under test with airtight plugs and brace to prevent slippage and blowout_ Furnish one plug with an inlet tap or other provision for connecting an air hose. Equip the air supply hose, connected between the air compressor and the plug, with a throttling valve, an air bleed valve and a high pressure shutoff` valve far control. Equip the low; pressure side of the throttling valve with a tee for a monitoring pressure gauge, protected by a gauge cock. This cock is kW closed except when the pressure lass is being timed. If the pipeline is submerged ender groundwater, the back pressure, caused by the wafer head, is measured and added to the standard test pressures to compensate for the groundwater effect on the air test. Sectim t0273U — 6' Edi6 m SANrrAFLY SE4 = COLLET 0-N SYSTEM Page 1t7 of 15 4. Apply air slowly to the pipeline until the pressure reaches 4.0 psig(27.61). Throttle the air supply to maintain the internal pressure benxeeu 4.0 and 3.5 psig (27.6 -24.1 j) for at least 2 minutes. Durinf this time check the plugs with soap solution to detect any plug leal€age. When the pressure reache s exactly 3.5 psig (24.1 i), disconnect the air supply, start a stop watch and record the time for the pres sure to drop to 2.5 psig (17.2 j). The +uini,mun time allowed far the pressure drop is computed on an air loss rate of 3.5 cfaa (5.9m 3 /min) or an air loss rate of 0.0030 cubic feet per minute (ef n) per square foot (G. D55 m 3 -min per square meter) of inner pipe surface area under test, whichever rate yields the least time for the pressure drop_ Should the time of the pressure drop between 3.5 and 2.5 psig (24.1 - 17.2 j) be less than the allowable specified time, make the necessary leakage repairs and repeat the air test. 6. Standard Drawing 02730-1 provides a nomograph which maybe used to compute testing times for air testing_ The nomograph computes results based upon English (U.S. Customary) units. For single pipe size test sections, the length limits :Car minimum test times obtained from Standard Drawing No.02730-1 entitled "Nomograph for Air Testing Crra-tty Sewer Mains" are contained is the following table_ T BIX 3.1 LENGTH LDHF FOR MEN-BICJ-M TEST TMES Pipe Diameter, Inches (Cm) Test Section Length_ Foot (m) N inimum Maximum 4 10 642 19b 1174 43 6 15 429 131 7-51 29 S 2U 322 98 564 172 1 25 257 78 450 13, 12 30 215 6b 37 11 ; 15 38 172 52 3D0 9.1 18 46 43 44 1250 21 53 123 37 215 66 24 61 107 33 18857 For test sections that are shorter than the minummi lengths_ new test tunes must be calculated_ This is done by multiplying the test time from the nomograph by the actual length of the test section (in feet) and then dl,k%ding the resultant product by the minimum test section length from the preceding table. Section 02730 — 6h Fditiam SANITARY SEWER COLT. [)-N MTEM Page 11 of 15 TABLE 3. DEFLECTION TESTDLIMFFATIONS Minimum Period Bet"Ten Trench Backfilliag & Testing Minimum Mandrel Diameter as a Percent of Inside Pipe Diameter " Days 95.0 30 Da , 92.5 .Mandrels moult have at least nine arms- Perform the mandrel test without mie chanical pulling devices. I. Material and Equipment for Testing Furnish all labor, equipment and materials (including water) necessary for performing the sewer line tests at Contractor expense. 3.5 % ATER AND SE%TR MAIN SEPARATION A_ Horizontal and veriical separation between water and seiner mains, is dictated by .-iontama Department of Environmental Quality. PART 4: ]1EASLIRE]>ENT _ILND PAi'11FNT 4.1 GENERAL A_ The f>alla%ing items are the pay items for the work covered under this section. Pa�,;ment for these items is full compensation for providing all materials, tools, labor and equipment necessary to c omplete the item and all incidental work related thereto_ whether- specifically- mentione d herein or not_ 4.2 SUi TR MAINS A_ h1easuremient of sewer mains are made in Lineal feet (rueters) of the various sizes and classes along the centerline of pipe from center to center of manholes. Pavment for sewer main is made at the contract unit price bid per lineal foot (meters) of the various sizes and classes called for, which includes furnishing and installing pipe, trench excavation and backfilL. furnishing and placing Type 1 pipe bedding, specials required for connection to manholes. testing and all other work necessary or incidental for completion of the items_ Sectiao orm — 6h Edi6 m SANifARY SE4f-C10LLE 0-N SYSU24 Page 13 of 15 4.3 MANHOLES A_ Mea suiement of each manhole for payment is made in tnwo parrs: (1) for a basic manhole, and (2) for any additional vertical height over and above the basic depth. A basic manhole is defined as being 5 feet deep (1.5 m) from the lowest invert to the top of the manhole frame and cares. Any manhole less than 5 feet deep (1.5 m) is considered as one basic manhole. B_ Any manhole over 5 feet deep (1.5 m) is considered as one basic manhole plus a vertical height measm-ement to the nearest 0.1 foot (0.03 m). Basic manholes are measured by numerical count and the additional vertical heights feet (meters) of manhole. The measurement of the additional vertical height -of manhole is the vertical height of the manhole from the lowest invei# to the top of the cast iron frame minus 5 feet (1.5 m). C. Pa mient for furnishing and installing a basic manhole, complete in -place, is made at the contract unit price bid per each for "Basis Manholes", 5.0 feet deep_ Such pa- meut includes base, manhole sections, steps, cast iron ring and cCR-er, joint sealer and all other incidentals required to complete the item. D. Paymxent for furnishing and installing manholes deeper than the basic manhole depth is made at the contract unit price bid per-outical foot (meter) for "Additional Manhole Depth-' and includes manhole sections. s"s.. joint sealer and all other incidentals to complete the item - Payment is made under a. Basic Manhole, T-0" (1.5 meter) Depth - Per Each. b. Additional Manhole Depth - Per Vertical Foot (meter). A. Measurement is made along the pipe from the tee or wye of the retain sewer through tees, wyes and other fittings to the street margin or right-of-wav margin. Measurement is to the nearest foot (G.3m)_ Payment for ser-Aces is based on the fallowing bid items as specified in the contract: a. Trench excavation and backfill is included in the linear foot price bid for se;firer service pipe. b. (size) (class) Seiner Service Pipe in Place," per linear foot_ Section 02730 — 6" Edih m SANITARY SEWER CO=CnDV SYSTEM Page 14 of 15 For test Sections exceeding the maximum lengtlis, either shorten the test section to an allowable length -or use the - vater test. F. Number of Tests Perform the niunber of leakage tests directed by the Engineer to assure that materials and workmanship are acceptable. Repair defective joints using only approved methods. Replace pipe having cracked or broken barrels. Do not exceed 800 feet (240 m) of sewer line per test uflless otherwise approved. G. T-V_ Inspection All seiner mains shall be inspected using a television camera before final acceptance. A sewer hue is deficient and unacceptable if (l ) the alignment is ontside the specified limits, (2) water ponds in any section are equal to or greater than 2 tunes the grade tolerance specified herein under Section 02730.3.E_1, or (3) the pipe has -visible defects such as open joints, pinched gaskets, cracked barrels of bell, or similar defects. Pay all costs incurred in any telex isi,om inspection performed solely- for Contractor benefit_ Record all television inspections in a format acceptable to the Owner_ Pull the camera through the server at 30 feet per minute (9 meters per minute maximum). If the c amera is pulled by attaching to the hose of a hydraulic sower cleainer_ assure the hose is not active dieing the gulling process. H. Deflection Testing The Engineer mad- recinire deflection testing of all or any portion of a flexible pipe installation to assure the construction quality. Flexible pipe is pipe that will deflect at least 2 percent without any sign of structural distress. Conduct deflection tests, when performed on PVC pipe, meeting ASTM D3034- and satisfy either of the following deflection limitations: Sec ica 02730 — 6' Edi6 m SANTfr1RY SEWER CC=C nO-N SYSTEM Page 12 4f li # 4-.5 GENERAL A_ The contract bid prices are full payment for all labor_ materials, tools and other incidentals as maybe required to complete the items of work in the Contract. END OF SECTION Sectiao 02730 — & Editiam SA ITAXY SEWER COI I.E C)N SYSTEM Page 15 of 15