underground utility location & sue...cardno, inc. director of utility market & practice...

Underground Utility Location & SUE

Jim Anspach, P.G. F.ASCE

Cardno, Inc.Director of Utility Market & Practice Development

http://www.mapps.org/

http://www.mapps.org/

35+ Million Miles of Underground Utilities in the US and Counting

US MAJOR OIL & GAS TRANSMISSION PIPELINE NETWORK

Records for legacy utilities are not comprehensive nor detailed/accurate

enough for project engineering purposes

Since Time Immortal, Surveyors have been recording visible utility features

on project maps• Some utility record

investigation?

• Connect the dots?

• More recently, call One-Call?

But, we don’t want to take responsibility for things we can’t see or measure

PLAN NOTES

1. Engineer and Surveyor take no responsibility for the accuracy and completeness of the utility information shown on these plans.

2. Utilities are depicted on these plans from records and visual observation. It is the responsibility of the contractor to verify all utilities before construction.

Incomplete and inaccurate maps of underground utilities between the structures lead to:

• Project construction surprises

• Delays

• Re-Design costs

• Damages

• Claims

• Change Orders

Pre 1980• One-Call just starting• Few devices for finding utilities• Few firms were mapping utilities• Utility Owners did “locating” for their own maintenance/repair

purposes• Finding Utilities was considered an “Art” or WITCHCRAFT

1979How Deep is that Utility?

• WGL Lawyer told employees they could only say “It’s So Deep”

• Ford Bacon Davis used Vacuum Trucks for anode installation

• Where is that utility in the 8” X 8” hole?

1983 Media General Contract

• Find and mark all utilities

• Expose all utilities in road crossings

1984 VDOT Project

• $1M in savings reported to FHWA

• $7M in savings reported “off-the-record”

• Markings surveyed by VDOT survey crews

Significant Advances in SUE

• Integrated Survey (1985)• WGL Union Stoppage (1986)• MD WSSC “Seal” requirement (1987)• CNA PL Insurance (1988)• VDOT Court Case (1989)• OR – 1st Design Ticket (in lieu of records)• FHWA Road Trip and Trials (1991)• “SUE” Association Talks Begin (1995)• ASCE 38 started (1996)

Standard Guideline for the Collection and Depiction of Existing Subsurface Utility Data

C-I /ASCE 38-02

“Engineer shall show utilities…”

Utility Investigations Vary:

> Records

> Visual Correlations

> Surface Geophysics

> Exposures and

Certified Record

Drawings

> Best Guess

But Depictions May Not:

> Utilities all shown on

the design plans the

same regardless of

method of

investigation.

Purpose of the Standard

– To assist owners and engineers in developingan unambiguous comprehensive scope ofwork concerning collecting and depictingutility information on documents.

– To standardize how utilities are portrayed ondocuments.

– And most importantly, to standardize anattribute for utility information that indicatesits reliability and quality (utility quality levelattribute).

These utility quality levels are used

– By Engineers – to make decisions on designing around existing utilities versus relocating them and to avoid redesign

– By Contractors – to determine construction bids and excavation methods

– By Project Owners – to retain a reliable map for future maintenance, security, or other needs

– By Courts – to allocate responsibility for errors and omissions and damages

“Quality Level D” (the least reliable data)

– Plotted on plans from records.

– Sometimes a field visit - to look for utility indications on the site - is made.

– Sometimes “verbal recollections” are plotted.

This level of effort is great for project planning purposes, utility “inventories,” and very preliminary utility relocation cost estimates.

Curb / EOP

Curb / EOP

Water Record says 4”

pipe is two feet off of

curb

“Quality Level C” (the “traditional” utility depiction)

– Surface Appurtenances are surveyed andaccurately plotted on a current site plan

– Utility data from records (QL D) are correlated tothe appurtenances

Problems with records interpretations still exist: e.g.schematics, no appurtenances depicted, utilities notstraight between appurtenances, no records exist, andso on.

Curb / EOP

Curb / EOP



curb

Curb / EOP

Water Record says


curb, but…

Valves are six feet off

curbSurveyed &

Plotted Water

Valves

Curb / EOP

Water Record says


curb.

Engineer makes

judgment that water

line depiction should

be moved.

Surveyed &

Plotted Water

Valves

Curb / EOP

Water Record says


curb.

Engineer makes

judgment that water

line depiction should

be moved. OR

RECONFIGURED

Surveyed &

Plotted Water

Valves

“Quality Level B” (a significant upgrade in quality)

– Surface Geophysical Methods used to search forand trace existing utilities.

– Designated utilities are then surveyed and plottedon site plan.

Non-recorded utilities found. Utilities’ routes betweenappurtenances are imaged.

Typically used in early preliminary design forconstruction footprint decisions.

Curb / EOP

Curb / EOP



curb

Curb / EOP

Water Record says


curb, but…

Valves are six feet off

curbSurveyed &

Plotted Water

Valves

Curb / EOP

Water Record says


curb

Designating indicates

otherwiseSurveyed &

Plotted Water

Valves

QL D and QL C

interpretations by

engineer were in error

“Quality Level A” (a guarantee in 3-D)

– Utilities exposed via non-destructive air-vacuummeans

– Exposed utilities are then surveyed and plotted onsite plan Elevations, Size, Condition, Materials,Precise Horizontal Positions are measured anddocumented

Typically used in final design stages. Allows smalladjustments in design for big savings in construction.

Ground

surface

Water line found at CL

Station 23+40, L10 to be

6 3/4” in diameter and

5.56 feet deep, slightly

corroded and cast iron

rather than ductile

The end result!

A map suitable for

current needs and

retrievable for future

needs with reliability of

the utilities clearly

indicated.

PLAN NOTES

1. Utilities are depicted on these plans in accordance with their achieved “Utility Quality Levels” as defined in the latest version of ASCE 38 (Standard Guideline for the Collection and Depiction of Existing Subsurface Utility Data).

2. Reliance upon these data for risk management purposes during bidding does not relieve the excavator or utility owner from following all applicable utility damage prevention statutes, policies, and/or procedures during construction.

3. It is important that the constructor investigates and understands the utility mapping scope of work between the project owner and their engineer regarding the types of utilities to be depicted and the project limits leading to these utility depictions.

DESIGN

ENGINEER

Without SUE With SUE

TOTAL RISK

RISK ELIMINATED

SUE

ENGINEER

D C B A

DEFINED QUALITY LEVELUNDEFINED QUALITY LEVEL

TOTAL ENGINEERING RISK POOL ALLOCATION OF RISK WITHIN ENGINEERING POOL

The total risk for the engineering pool decreases

as quality level increases, While within the

engineering pool, the risks shift towards the

subsurface utility engineer as quality levels trend

towards Quality Level A data.

How do you achieve a utility quality level ?

Quality Level D: Plotting from record

information

> Records research. How much?

> Is calling the One-Call adequate?

> Is a site visit necessary to look for utility

signs or appurtenances?

> Do I need to plot everything for which

there is a record? (e.g. individual

services, traffic control sensors?)

> What if there is an indication of a utility,

but no record?

How do you achieve a utility quality level ?Quality Level C: Correlation of records to surveyed

features / utility appurtenances

> Is using someone else’s survey of utility features

OK?

> How many surveyed features are required to call a

long run of utility Quality Level C?

> When does a Quality Level C line need to revert to

Quality Level D?

> Do I need to plot everything for which there is a

record? (e.g. individual services, traffic control

sensors)

> What if there is an surveyed utility feature, but no

record?

How do you achieve a utility quality level ?Quality Level B: Geophysics + Survey

> Is using someone else’s survey of utility marks

OK?

> What geophysics should I use?

> Do I search for a specific utility, or for

everything?

> How do I handle signals that are unknowns?

> How do I handle gaps in geophysical signals?

> What level of effort do I need to go to if I can’t

find a utility of record?

> Do I need to get into all the manholes and

vaults?

> To what Accuracy am I held responsible?

How do you achieve a utility quality level ?

Quality Level A: Exposure + Survey

> Does it matter what I use to excavate?

> What if I don’t find anything?

> How deep should I go?

> What if I find something different than I

thought was there?

> Can I trust someone else to survey my

patch and record the data?

> Do I need to convert to an elevation?

> To what accuracy am I held responsible?

> Water vs. Air vacuum?

ASCEACECNSPECSINUCAABAAWWAAIACMAAACSMWWEMAIMLAUSDAXLVOSCO

Engineering Series Contracts

Owner-EngineerEngineer – Sub-ConsultantEngineer – Geotechnical FirmEngineer - Surveyor

3D Model of Existing Facilities

3D Mapping and Marking of Underground Utilities during Project Development and

Delivery

Utility Line Profile View


Delivery85


Delivery86


Delivery87

Locations with QLA Data


Delivery88

Test hole Test holeValve

Manhole

Assumed Curved Pipe Alignment


Delivery89


Manhole

Assumed Straight Pipe Alignment


Delivery90


Manhole

Assumed Horizontal Interpolation


Delivery91


Manhole

3D Model Including Utilities

92

ATTRIBUTESQuality LevelMethod of “z” valueStarting elevationEnding elevationSizeMaterialOwnerConditionAgePressure

3D Utility Visualization – Ireland


Delivery93

New Adventures Coming

• ASCE Utility “As-Built” Standard

• New SHRP Tools

• Utility Engineering and Surveying Institute

– SUE Training and Certifications

– “Utility Engineer” Education

– Utility Risk Envelopes

Senate Bill No. 481–Committee on Government AffairsCHAPTER..........

AN ACT relating to local governments; prohibiting a county,incorporated city or regional transportation commission fromcreating, maintaining or displaying a comprehensive modelor map of the physical location of all or a substantial portionof the facilities of a public utility, public water system orvideo service provider; providing that the prohibition doesnot limit the authority of a county, city or regionaltransportation commission to require a public utility, publicwater system or video service provider to discloseinformation relating to the physical location of the facilitiesof the public utility, public water system or video serviceprovider to facilitate certain public projects; revisingprovisions relating to municipal utilities; and providing othermatters properly relating thereto.

Lessons learned from Las Vegas RTC

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