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HomeMy WebLinkAboutWQ0041548_Sewer Extension Permit Status Update_20220321INCDENRIDWR Rik NEW BERN CITY OF NEW BERN DepaLtLuent of Public Utilities Water Resources 527 NC Hwy. 55 West, P.O. Box 1129 New Bern, NC 28563-1129 (252) 639-7526 March 21, 2022 Mr. Robert Tankard Surface Water Protection Section Division of Water Quality — Washington Regional Office 943 Washington Square Mall Washington, NC 27889 Subject: Permit No. WQ0041548 Engineer's Certification Dear Mr. Tankard, MAR 2 9 2022 Water Quality rtaglonal Operations S-vIton Washington Regwnu vmce The City has recently completed and tested all of the proposed sanitary sewer improvements as described in the referenced Wastewater Collection System Extension peiuiit. Enclosed please find the following documents as certification that the project has been completed in accordance with the conditions of the approved permit: 1. Engineer' Certification 2. Issued Record Drawings for the Project (24"x36") 3. Technical Specifications for the Project Please feel free to contact me at (252) 639-7527 if there should be any questions or if additional information is needed. Enclosure Sincerely, Jordan B. Hughes, P.E. City Engineer Everything comes together here. CERTIFICATION CHECKL T ��VEDRvcc� To be completed by the certifying engineer prior to operation of the permitted sewers, per 15A NCAC 021116!" Certifying Engineer: 3' 9 AI l$ 3 rIl S Certification Review Date: 10/211tt Project Name: Lift Station No. 29 Rehabilitation Permit No. WQ0041548 Project County: Craven 1) Has permittee information changed since the permit was issued (or last modified): change of mailing address, change of ownership, transfer from developer to HOA/POA, etc. n Yes 1{'No • If yes, please provide either a change of ownership form or new contact information. Note that transfer of permits from the developer to the HOA/POA must occur with the first certification. 2) Have the as -built drawings have signed, sealed, and dated by an N.C. PE? Ees ❑,No 3) Final Engineering certification? beees n No .. • If Partial Engineering certification, provide detailed narrative induding""what .isbeing certified in the current phase, what was previously certified (if appli ble), and what is left to becertified. 4) Adequate information related to sewer lines: Yes n No n N/A • Three feet minimum cover has been provided for all sewers unless ferrous pipe was installed. • Minimum diameters for gravity sewers are 8-inches for public lines and 6-inches for private lines. • Manholes have been installed: At the end of each line, at all changes in grade, size, or alignment, at all intersections, and at distances not greater than 5 feet; minimum diameter shall be 4.feet (48-inches). 5) Adequate information related to pump stations: Yes n No n N/A K . • Ensure power reliability option was selected per 15A NCAC 02T.0305(h). 6) Was project construction completed in accordance with all of the following: Yes MAR 2 9 2022 Water ClunIty rfogiirsIL'' ns Section 1)4-Unal Office No ❑ N/A • 15A NCAC 02T, Minimum Design Criteria (MDC) for the permitting of Gravity Sewers (latest version), and MDC for the Permitting of Pump Stations and Force Mains (latest version)? If not, a variance approval is required in accordance with 15A NCAC 02T.0105(b), prior :tacertification and operation. • Contact the Central Office to discuss the variance to determine a course of action: • Applicant must submit two copies of the variance request form, plans, specifications, calculations, and any other pertinent information to the Central Office (one hard copy, one digital copy). • The central office will review the variance request, and if approvable, specific language regarding the variance will be incorporated into the permit, either via a special condition or a supplementary letter. A copy of the reissued permit with variance language or the variance letter must be maintaine with the original documents. 7) Does the project contains high priority lines (15A NCAC 02T .0402(2))? ❑Yes No • If yes, ensure that the permit already contains the necessary condition related to high priority lines 15A NCAC 02T.0403 (a)(5). If the permit does not include this language, the Fast Track reviewer will reissue the permit with the appropriate language. 8) Are Permit modifications are required for any changes resulting in non -comp ' nce with this permit (including but not limited to pipe length changes of 10% or greater, change in flow, pump n design capacity design change of 5% or greater, and/or change in the number/type of connections)? ❑ Yes No • If yes, a permit modification request must be submitted to the appropriate Regional Office, and a modified permit with revised certification must be issued prior to certification and operation.. NC DWR — Water Quality Regional Operations Section 943 Washington Square Mall, Washington, NC 27889 Washington Regional Office Phone: (252)-946-6481 FAX: 252-946-9215 FAST TRACK SEWER ENGINEERING CERTIFICATION PERMITTEE: PERMIT #: PROJECT: ISSUE DATE: City of New Bern WQ0041548 Lift Station No. 20 Rehabilitation March 16, 2020 This project shall not be considered complete nor allowed to operate in accordance with Condition 7 of this permit until the Division has received this Certification and all required supporting documentation. It should be submitted in a manner that documents the Division's receipt.'Send the required documentation the Regional Supervisor, Water Quality Regional Operations Section at the address at the bottom. Any wastewater flow made tributary to the wastewater collection system extension prior to completion of this Certification shall be considered a violation of the permit and shall subject the Permittee to appropriate enforcement actions. The Permittee is responsible for tracking all partial certifications up until a final certification is received. A Final Certification shall be a complete set of record drawings and design calculations regardless of whether partials have been submitted. PERMITTEE'S CERTIFICATION I, the undersigned agent for the Permittee, hereby state that this project has been constructed pursuant to the applicable standards & requirements, the Professional Engineer below has provided applicable design/construction information to the Permittee, and the Permittee is prepared to operate & maintain the wastewater collection system permitted herein or portion thereof. Clary Printed Name, Title Signature Date ENGINEER'S CERTIFICATION I, BAN S. NJ& I1 3 , as a duly registered Professional Engineer in the State of North Carolina, having been authorized to observe (periodically, n weekly, I I full time) the construction of the project name and location as referenced above for the above Permittee hereby state that, to the best of my abilities, due care and diligence was used in the observation of the following construction: a 84--gallon per minute pump station with duplex pumps, on -site audible and visual high water alarms, telemetry, and a {portable generator receptacle with telemetry OR permanent generator with automatic transfer switch}; as well as approximately 1325 linear feet of 4-Inch force main to serve as part of the Lift Station No. 29 Rehabilitation project that collects domestic and commercial wastewater into the City of New Bern existing sewerage system; such that the construction was observed to be built within substantial compliance of this permit; 15A NCAC 02T; the Division of Water Resources' (Division) Gravity Sewer Minimum Design Criteria adopted February 12, 1996 as applicable; the Division's Minimum Design Criteria for the Fast -Track Permitting of Pump Stations and Force Mains adopted June 1, 2000 as applicable; and other supporting materials. North Carolina Professional Engineer's Seal w/signature & date: \-\\i }C q/// -4177 cit- • • �O!/��i � • OES���e FBI Final El Partial (include description) 'Q SEAL r-; 1 • 0::"") 29 Certification Comments/Qualifiers (attach if necessary): NC DWR — Water Quality Regional Operations Section 943 Washington Square Mall, Washington, NC 27889 fig CEIVEDMC p/oyyp 4 j of New Bern Water Resour; Pump Station Design Calculations MAR 2 9 2022 Project: IS# Rebuild Date: 11-Feb-20 Quality Regi�r^^,' Uperatlona Section Review: J • ff office I. Wastewater Flows: A. Flow from Exisitng Users 15,000 gpd B. 15,000 gpd C. 0 gpd D. 0 gpd Total Flow Tributary to Proposed LS = 30,000 gpd H. Peaking Factor: * Peaking factor calculated using NCDENR recommended formula of PF = (18 + IP)/(4 + -VP), where P is the service population. Service population is calculated assuming 75 gpd per person. Proposed Flow: 30,000 (/ 75) = Service Population (P; 400 Calculated PF: 4.02 III. Pumping Rate: Average Daily Flow: 30,000 gpd = Peak Flow: 120,600 gpd = Design PF: 4.02 20.83 gpm 83.75 gpm Design Pumping Rate: 84 gpm IV. Velocity in Proposed Force Main: * Wastewater velocity occurring in the proposed force main system is calculated using the continuity equation: V = (0.409Q)/D2 Proposed Force Main Size: 4 in Velocity of Wastewater: 2.14 fps > 2.00 fps, Velocity O.K. Page 1 of 7 (_ f of New Bern Water Resoun. Pump Station Design Calculations V. Cycle Times and Active Storage. * Active storage shall be calculated using V=TQddf(1-Qddf/Q ). Cycles per hour shall be 4 and the time (T) between cycles shall be 15 min. Qd 21 gpm QinanP 84 gpm T 15 min. Active Storage (V) 236 gal. VI. Wet Well Dimensions and Float Elevations: Wet Well Diameter: Volume Per Vert. Foot: 4 ft 94 gal/ft Required Storage Depth: 2.51 ft Rim Elev. Invert of Influent High Level Lag Pump On Lead Pump On Pumps Off Low Level Wet Well Bottom 18.50 10.90 10.90 At the influent invert 10.40 0.5' below the High Level setting 10.20 0.2' below the Lag Pump On setting 7.69 Lead Pump On - Req. Storage Depth 7.19 6" below the Pumps Off setting 5.19 Level to completely submerge pumps, 2.5' below Pumps Off setting. Note: Additional storage depth provided Page 2 of 7 C, of New Bern Water Resourn Pump Station Design Calculations VII. Lift Station & Force Main Piping: A. Lift Station Piping: Pipe Dia: 4 in Item No. of Units L/D Ratio Equivalent Length Straight pipe 9 - 20 45° bend 0 16 0 90°bend 2 30 20 22.5° bend 0 9 0 Branch Tee Flow 1 60 20 Check Valve 1 135 45 Gate Valve 2 17 11' Total Equivalent Length: B. Force Main Piping: Pipe Dia: 4 in 116 ft Item No. of Units LTD Ratio Equivalent Length Straight pipe 1400 - 1400 45°bend 2 16 11 90°bend 2 30 20 22.5° bend 0 9 0 Branch Tee Flow 1 60 20 Check Valve 0 135 0 Gate Valve 1 17 6 Total Equivalent Length: C. Total Equivalent Force Main Length: 1457 ft Total Length of Lift Station Piping: 116 ft Equivalent Force Main Diameter Length: 116 ft of 4 inch pipe Total Length of Force Main Piping 1457 ft Total Equivalent Length of Force Main 1,573 ft Page 3 of 7 C of New Bern Water Resouri, Pump Station Design Calculations VIII. Design Point for Pump Selection: A. Static Head: The proposed force main will discharge into the common force main located along Racetrack Rd. This 6" FM is short in length and only has one other pump station that discharges to it. The distance from the tie-in point the discharge end of the common FM is only 520', so for the purpose of the head calculation, the 520' of 6" FM is been added to the total FM length as 80' of 4". The static head due to elevation will be the difference between the high point in the force main and the "pump off" elevation in the wet well, which is (18.30'). Static Head (discharge) Static Head (elevation) All LS On Only Proposed LS On 5.00 ft 0.00 ft 18.30 ft 18.30 ft Total static Head 2330 ft 1830 ft B. Dynamic Head Loss at Design Pumping Rate: * Dynamic Head loss shall be calculated using the Hazen -Williams formula: hf = L [(10.44Q ^ 1.85)/(C ^ 1.85 *D ^4.87)], assuming C=120 for the PVC force main. L = Total equivalent length of force main piping. QPrimP 84 gpm L 1573 ft D 4 in. C 120 h f (design punip rate) 9.93 C. Design Point for Pump Selection: The design point for the pump selection will be the design pumping rate at the and corresponding system head. Design,Bohit 84 gpm @` . 33 ft.;TDH Page 4 of 7 C • of New Bern Water Resoun Pump Station Design Calculations IX. Pump Selection: The following pump will be used for the proposed project. • NP 3102 MT 3- Adaptive 464 Prtericd scr.p &1 icartWhendarvrrll411 kkelfor P+aaWr!b ram inter3pPYntiom. Pont* to be mire drd with W W-phr. for f+m better dsa►u r slParu. MWog rbased Or* nwith high 403pdooe4redi. Technical specification Corrftu nkto n Cwvu rrmdmta a xylem trmrd Water, pme naoa,3P.2 F,62.41411P,L689t6-5it'/i .ki !I' r - I I i I I ,�� -J a i I\.r_. i I i � I 0 102 211 Jp 433 ESA 140 IN co comu S Mrear we64r tateratl.. Mo llltmnm IAU.NL-10 P-Sifal poltratien, Wit Shp prFr*imp nr , tOsdr+V� rn 161 armi t6 Pump information Materials IrprfrrlbNter 102 ram Obmeryr noottrr 31.SA6loch Ykttiam.r !maw Iardkon" Smv kanIna orextl Ow oral bon [mtriby LW Wdwr cra d m 717PRO 100 me 1745 rpm 61e44 mrrd rrd 7 lhpfrrt Nod Page 5 of 7 �. of New Bern Water Resour Pump Station Design Calculations .X. System Curve: Flow (gpm) System Head ('1'DH) All LS On System Head (TDH) Only Proposed LS On Pump Head (TDH) 21 24 19 44 42 26 21 42 63 29 24 41 _ 84 33 28 39 t 105 38 33 38 126 44 39 38 147 51 46 36 60 50 40 30 20 10 0 .• 407 s .0• -' 0. i '-• i s s �- O 50 100 150 Flow (GPM) • System Condition Qrd (gpm) All LS n 105 Only Proposed LS On 120 XI. Actual Pump Cycle Times: Wet Well Diameter 4 ft Pump On Elev. 10.20 ft Pump Off elev. 7.69 ft Active Storage 236 gal 200 Pump Curve --— BothLSOn Only Proposed LS On System Condition Fill Time (min.) Pump Tim mi Cycles per Hour Both LS On 11.33 2.8 4.25 • Only Proposed L,S Or 11.33 2.38 438. Page 6 of 7 C. of New Bern Water Resourc Pump Station Design Calculations XII. Buoyancy Calculations: * Water table is assumed to be at an elevation 6" below the wet well rim elevation. y water = 62.4 lbs/ft3 yconcrete = 150 lbs/ft' sotl = 120 lbs/ft3 Wet Well I.D. 4 ft Wet Well Wall Thck. 6 it Wet Well O.D Extended Base Dia. 6.00 ft 5.00 ft Wet Well Rim Elev. 18.50 ft Wet Well Bottom Elev. 5.19 ft Top Slab Thck. 10 in Extended Base Thck. 8 in A. Force of Water Displaced by Wet Well Structure: Volume of Riser Sections Volume of Extended Base Total volume of Wet Well 261 ft3 19 ft3 280 ft3 Total Force of Water Displaced 17,472 Ibs B. Weight of Saturated Soil Above extended Base Section: Volume of Soil Above Ext. Base 115 ft3 Density of Saturated Soil 57.6 lbs/ft3 Weight of Soil Above Ext. Base 6,624 lbs C. Weight of Concrete in Wet Well Structure: Weight of Riser Sections Weight of Extended Base Weight of Top Slab 14,112 lbs 2,850 lbs 1,963 lbs Total Weight of Concrete 18,925 lbs D. Protection Against Buoyancy: Total Buoyant Force Total Reactant Force 17,472 lbs (ysoil = 1201bs/ft' - y water = 62.4 Ibs/ft ) 25,549 lbs > Buoyant Force, O.K. Factor of Safety 1.46 Page 7 of 7 OT a em brand Pump Startup Report Xylem Water Solutions USA Inc. 14125 South Bridge Circle Charlotte, NC 28273 Voice 704-504-8804 - - - Fax 704-504-8773 ,yG}T a xylem brand Report Date: January 13, 2021 I Purchase Order No.: 1 I Delivery NotE - - Pump Serial Numbers: ,2010278 & 2010279 Model No.: ,3102.060-0217 Start -Up Date: jJanuary 6, 2021 I Control Panel Mfgr: I . Project Name: 1LS-29 Project Location: NEW BERN N.C. Start -Up Technician: ;ALLEN ETHEREDGE FUS# IC84183 Engineer's Contact (CITY OF NEW BERN Phone: i262-639-7640 Engineer. 'CITY OF NEW BERN Contractor's Contact CITY OF NEW BERN Phone: 1 Contractor. ICITY OF NEW BERN (INSTALLED End User's Contact iCITY OF NEW BERN Phone: End User. ,C17Y OF NEW BERN VOLTAGE & CURRENT 'CHECKS FLA: , . 13 HP: 1 6.0 GPM: 1 • 86 TDH: 35 VOLTAGE: 230 PHASE: 3 VOLTAGE UNITS OFF: L1-L2: 249 L1-GND: 123.6 L2-L3: I 246 L2-GND: 216.4 L1-L3: 247 L3-GND: 124.3 VOLTAGE UNITS ON: UNIT NO. 1: UNIT NO. 2: UNIT NO. 3: L1-L2: I L1-GND: L1-L2: L1-GND: , 1 L1-L2: I L1-GND: j L2-L3: L2-GND: L2-L3: L2-GND: ; L2-L3: L2-GND: L1-L3: L3-GND: 1 L1-L3: L3-GND: i L1-L3: L3-GND: CURRENT: UNIT NO. 1: UNIT NO. 2: UNIT NO. 3: L1: i 10.5I 1 L1: 10.3, L1: L2: 9.9, L2: I 10.0! L2: L3: I 9.91 L3: 9.81 L3: ' I UNBALANCE CALCULATIONS VOLTAGE UNIT NO. 1: UNIT NO. 2: UNIT NO. 3: AVERAGE I AVERAGE I I AVERAGE ' MAX. DEV. I MAX DEV. I i MAX DEV. , UNBALANCE I UNBALANCE I I UNBALANCE i UNBALANCE CALCULATIONS CURRENT UNIT NO. 1: UNIT NO. 2: UNIT NO. 3: AVERAGE 10.1 AVERAGE 10.01 AVERAGE 1 MAX DEV. 0.2 I MAX DEV. , 0.21 • MAX DEV. I UNBALANCE I 1.98% UNBALANCE I 2.33%I I UNBALANCE I 1 DRAW DOWN TEST . , MANHOLE DIAMETER = 6 FT = 211.49 GAL/FT DEPTH PRESSURE GAUGE READING 60 SEC. DRAWDOWN = 6.60 IN. = PUMP RATE OF 96.93 GPM FOR UNIT 1 psi 60 SEC. DRAWDOWN = 6.00 IN. = PUMP RATE OF 105.75 GPM FOR UNIT 2 psi SEC. DRAWDOWN = IN. = PUMP RATE OF 0.00 GPM FOR UNIT 3 psi AVG PRESSURE READING , #DIV/01 FT GAUGE ELEV FROM WATER LEVEL I FT TDH #DIV/01 , FT STATION CONTROLS TYPE OF CONTROLLER NONE APP 500 APP 700 ; OTHER PLC: Msmart yes TYPE OF LEVEL SENSOR FLOATS ,x PROBE ix U.SONIC I PRESSURE i OTHER SENSOR(S) ACTUATE? yes CONDITION OF STATION CONTROL PANEL: (clean, functioning as designed. GUIDE RAILS PLUMB?: yes PUMPS RIDE RAILS: yes PUMPS CLEAR HATCH: yes GENERAL NOTES: 1 3/21/2022