How SUE Can Provide for Better Design, Cost Savings, and Damage Prevention for America s Future Infrastructure Improvements

Transcription

1 Hw SUE Can Prvide fr Better Design, Cst Savings, and Damage Preventin fr America s Future Infrastructure Imprvements CI/ASCE & Subsurface Utility Engineering By James F. Nne, PE, M.ASCE jnne@bsieng.cm (617)

2 Brief Histry East & West Shaking Hands

3 Brief Histry Glden Spike Recreatin

4 Brief Histry Reenactment

5 Brief Histry Winter Steam Festival

6 Brief Histry First Transcntinental Telephne Line

7 Brief Histry First Transcntinental Telephne Line

8 Brief Histry First Transcntinental Telephne Line

9 Overview Subsurface Utility Engineering (SUE) What is SUE and why d we need it? Managing risks invlved with utility mapping. Why the Business as Usual mdel n lnger wrks. CI/ASCE What is the standard and wh develped it? Quality Level Based Utility Mapping. Respnsibilities f the Subsurface Utility Engineer. Gephysical prspecting equipment & techniques. Use f SUE in the Mapping and Design Prcess When t use SUE and hw it applies t the design prcess. Utility cnditin assessment. Utility crdinatin & relcatin design. Hw t budget fr SUE, cst t benefit rati. Cnclusin

10 Subsurface Utility Engineering (SUE) Subsurface Utility Engineering (SUE) Branch f Engineering Practice that invlves managing certain risks assciated with the fllwing prfessinal services: Utility Mapping at Apprpriate Quality Levels Utility Crdinatin Utility Relcatin Design Utility Cnditin Assessment Cmmunicatin f Utility Data t Cncerned Parties. Utility Relcatin Cst Estimates Implementatin f Utility Accmmdatin Plicies Utility Design

11 Managing Risks Risks Invlved with Traditinal Utility Mapping Methds Withut prper utility risk management utility wners and facility manager s alike are left vulnerable t cstly prject delays and schedule ver runs due t: Inaccurate utility plan cmpilatin based slely n recrd data that may r may nt be available. Unknwn utility cnflicts discvered during the cnstructin prcess that culd have therwise been avided. Safety risks psed t cnstructin crews frm unknwn utility cnflicts encuntered during excavatin r bring activities. Utility service disruptins t the general public.

12 The Business as Usual Mdel Utility Mapping Cmpilatin Fr decades surveyrs and engineer s alike have relied n the Old Way f cllecting and depicting utility infrmatin. Cmpile Available Utility Recrd Data. N Warrant f Accuracy is Expressed r Implied. Infrmatin May nt be Available fr All f the Utilities. Cntractr t Verify All Existing Utilities. Creates a change rder rich envirnment. Leaves Prjects Wide Open fr Cnstructin Delay s and Re-Design s. Cntractr t Cntact Lcal One Call Center Prir t Perfrming Wrk (Dig Safe) N Way t Cntrl Quality r Accuracy f One Call Service Mark Outs. Nt All Utility Owners are Members f the One Call System.

13 CI/ASCE What is the Standard? New and emerging technlgies allw fr the cst effective cllectin and depictin f existing subsurface utility data. SUE has emerged in the past 30 years as a means t better characterize utility infrmatin. The Cmmittee is a Brad cllabratin by a diverse grup f experienced prfessinals and utility wners. The CI/ASCE Standard clearly shws hw t define quality attributes.

14 CI/ASCE Why Was it Develped? The Natin s infrastructure is in a state f cnstant expansin and deteriratin. EPA regulatins and new cnstructin have necessitated excavatin activities in area s f high utility density. Available utility right-f-way s are becming limited. Subsurface utilities create a large risk fr emerging infrastructure prjects. Pr utility data affects the ability t make infrmed decisins. New utility technlgies are prliferating the market Design challenges faced by engineers is greater than ever.

15 Quality Level Based Utility Mapping Utility Quality Levels Per the CI/ASCE Standard, each utility depicted n a plan shall be prescribed a quality level based n hw the infrmatin fr that particular utility was cllected. Replaces the Business as Usual Mdel with a cst effective methd f utility data cllectin. 4 Quality Levels as defined by CI/ASCE 38-02: Quality Level D Quality Level C Quality Level B Quality Level A

16 Quality Level D QL-D Utility infrmatin pltted n the drawings based slely n recrd infrmatin, individual recllectins r the existence f utility service.

17 Quality Level C QL-C Utility infrmatin btained as abve fr quality level D, pltted t crrelate with surface utility features which have been field verified, survey lcated and accurately reduced nt the design/cnstructin dcuments. Prfessinal Engineering Judgement is used in interpreting the recrd infrmatin.

18 Quality Level B QL-B Utility infrmatin derived by establishing the surface hrizntal lcatin f a utility using Surface Gephysical Prspecting methds (Designatin). Interpretatin f the designatin results by an SUE prfessinal results in QL-B data. Results are reprducible. SUE prvider is liable fr results prduced.

19 Quality Level A QL-A Utility infrmatin which has been visually verified, survey lcated (bth hrizntally and vertically) and accurately reduced nt the design / cnstructin dcuments. Prfessinal Engineering Judgement is used t interpret the QL-A results.

20 Respnsibility f the SUE Engineer Prject Engineer / Prject Manager Shuld Advise the Prject Owner Educate the Prject Owner Recmmend a Scpe f Wrk Discuss Plan Deliverable Frmatting Discuss Incrpratin f SUE int the Design Prcess Prepare Utility Drawings Review Plans / Designs with the Owner. Make recmmendatins fr further investigatin wrk such as upgrading the quality level f specific utility infrmatin.

21 Respnsibility f the SUE Engineer SUE Deliverables Frmatting Per the CI/ASCE Standard, each utility depicted n the plan shall clearly state it s quality level. Determine file frmat fr deliverables.dwg r.dgn file types Establish plan sheet layuts Develp written reprts if required fr utility cnditin assessment Prvide digital media r CCTV data

22 Gephysical Prspecting Quality Level B Methds Prfessinal Engineering Judgement is always utilized t interpret the cllected gephysical prspecting data. Electrmagnetic Pipe and Cable Lcatrs Grund Penetrating Radar Gradimetric Measurements Acustic Emissin, Micr gravitatinal Techniques Metal Detectrs Istpic (Radimetric) Techniques Terrain Cnductivity Chemical Techniques Resistivity Methds Optical Methds Brehle Gephysics and Gephysical Diffractin Tmgraphy Infrared (Thermal) Methds X-Ray Methds (Penetrating Radiatin) Ttal Field Measurements

23 Gephysical Prspecting Electrmagnetic Pipe and Cable Lcatrs Electrmagnetic Frequency pipe lcatin methds prduce the mst cnsistent and viable designatin results Utilizes radi frequencies t induce signal t utility. Allws fr direct cnnectin t utility fr signal inductin. Utility must be metallic.

24 Gephysical Prspecting Electrmagnetic Pipe and Cable Lcatrs Cnt. The experience f the SUE Technician is crucial t the success f the utility investigatin prcess. Ability t islate signals and create reprducible results. Existing utility recrd infrmatin is nt required t perfrm designatin services. Paint r flagging placed at pint f peak signal strength.

25 Gephysical Prspecting Grund Penetrating Radar (GPR) Sends Micrwave Pulses int the grund and measures reflectin received back at grund surface. Frequency ranges f 10 t 1,000 MHz. Sil cnductivity, dielectric cnstants directly affect results. High cnductivity sils, areas with heavy salt use, r thick pavement will greatly affect the depth f signal penetratin. Is able t lcate bth metallic and nnmetallic utilities. Cannt lcate utilities smaller in diameter than their depth in feet.

26 Minimally Intrusive Excavatin Air Vacuum Excavatin Vacuum excavatin is a very ppular test pitting methd utilized t btain quality level A infrmatin withut fear f damaging the existing infrastructure. Utilizes cmpressed air t lsen sil Sil is then extracted with a vacuum hse and depsited in a hlding tank Once the utility is expsed the excavatin spils are replaced and cmpacted.

27 QL-A Data Example f Quality Level A Test Hle Lg With Multiple Data Pints

28 Review f Quality Level Definitins QUALITY LEVEL D QUALITY LEVEL C QUALITY LEVEL B QUALITY LEVEL A

29 Use f SUE in Mapping & Design When t Use SUE and hw it applies t the design prcess Engineer s and Surveyrs need t prperly define the prject specific SUE needs at the nset f any given prject prir t the cmmencement f engineering services. Quality Level D Data is use fr planning Quality Level C Data is used fr cnceptual design Quality Level B Data is used fr preliminary design. Quality Level A data is used fr final design. Depending n the prject requirements, any r all Quality Levels may be apprpriate at any phase f a prject. Data May als be gathered as a prject prgresses.

30 Use f SUE in Mapping & Design Quality Level B Mapping Phase The existing utilities are electrnically designated, survey lcated and the results are accurately reduced n the prject base plans. Lcatin f the preliminary alignment is revised t avid cnflicts with existing utilities where pssible. Based n the revised alignment and the quality level B utility infrmatin; precise lcatins may nw be selected fr exact hrizntal and vertical infrmatin data cllectin. (QL-A Data Pints)

31 Use f SUE in Mapping & Design Quality Level A Phase Quality Level A data is cllected by either traditinal r nn-destructive test pitting methds. The infrmatin is then accurately reduced nt the engineering dcuments. QL-A Data is pltted n a test hle lg prfile shwing the exact utility lcatins and sizes. The prpsed imprvements can nw be designed t minimize the impact n existing utilities. Infrmed decisins can nw be made where utility relcatins are required.

32 Use f SUE in Mapping & Design Utility Cnditin Assessment Nw that the gephysical data has been cllected and depicted n the prject dcuments, we can turn t ther nn-destructive means f utility cnditin assessment fr additinal utility data cllectin. CCTV Pipe Inspectin Rbtic CCTV Inspectin Crawlers Push Rd Camera Systems

33 Use f SUE in Mapping & Design Utility Cnditin Assessment Cnt. Ultrasnic Pipe Testing Measures Existing Pipe Wall Thickness fr irn and steel pipes. Primary methd fr determining useful remaining pipe life.

34 Use f SUE in Mapping & Design Utility Crdinatin and Relcatin Design All infrmatin pssible t btain thrugh SUE techniques has nw been cllected and depicted n the prject dcuments. Cntact the affected utility cmpany as early as pssible. Cnsider the relcatin design f the utilities affected. Determine mst cst effective way t address utility cnflicts. Develp a utility relcatin plan r a prpsed design mdificatin.

35 Use f SUE in Mapping & Design Cmmunicatin f Utility Data t Cncerned Parties Let the cntractr knw hw the utility infrmatin was btained Include Quality Level Based mapping in the cnstructin dcuments. Utility Relcatin Cst Estimates Cnsider the cst f frcing a utility t relcate. Ttal prject cst cncept & reimbursement plicy.

36 Use f SUE in Mapping & Design Hw t Budget fr SUE On average, the SUE budget fr mst DOT prjects wrks ut t be apprximately 1% - 2% f the ttal prject cst. On average, fr mst DOT based prjects, the SUE cmpnent shuld cmprise f apprximately 10% - 20% f the ttal design budget. SUE is very prject specific and requires an individual prject apprach. Prject Cst Savings $4.62 in savings fr every $1.00 spent n Subsurface Utility Engineering* *(Purdue University Study,1999)

37 Use f SUE in Mapping & Design 100% Guarantee??? Can a 100% guarantee be prvided as t the lcatin f undergrund utilities fr a particular area? The simple answer is yes 100% guarantee fr a particular area requires expsure f the entire area using nn-intrusive methds. This leads t csts far abve the ptential savings and reduced risk f damage. Expsure is als necessary t prve the nn-existence f utilities fr example at prpsed bring lcatins, using vacuum excavatin t ensure that utilities are nt damaged.

38 Cnclusin Significant cst savings and preventin f damage t utilities will result frm apprpriately managing the risks n a prject. Subsurface Utility Engineering, as a branch f engineering practice prvides a means t manage these risks. At each stage f a prject the risks, impacts and csts shuld all be assessed and the ptimum slutin determined. A qualified Subsurface Utility Engineer, as defined by ASCE can be f great assistance in this prcess. When assessing csts, cnsideratin shuld be given t indirect csts nt directly attributable t the prject and csts t entities ther than the prject wner. Damage preventin measures can nly happen when the risks are fully understd and accunted fr.