Before You Dig: Underground Services Risk Guide for Sydney Sites

One unverified service can stop excavation before the first planned stage is complete. A cable strike may expose workers to electrical hazards. A damaged water main can flood the work area. Contact with a gas service may trigger an evacuation, emergency response and long site shutdown.

A safe before you dig Sydney process starts well before machinery enters the excavation zone. It requires current asset information, a clear site inspection, competent locating, service exposure and a work method understood by every person involved.

Before You Dig Australia (BYDA) gives project teams access to plans and safety information supplied by registered asset owners. These plans are an essential starting point, but they do not confirm the exact position or depth of every underground service.

This guide covers the steps that builders, estimators, project managers, supervisors, and developers can use to manage excavation utility risk across Sydney sites.

Key Takeaways

Never treat BYDA plans as proof of an asset’s exact location. Use them to guide locating, marking and potholing.
Wait for every affected asset owner to respond. Missing information can leave a major gap in the site risk review.
Check beyond the excavation footprint. Plant movement, truck access, stockpiles and lifting work may affect nearby services.
Expose services before mechanical excavation reaches the risk area. Use suitable hand tools or non-destructive digging methods.
Brief every operator and subcontractor. A plan left in the site office does not control a live excavation risk.

BYDA and Record-Search Workflow

A practical BYDA excavation guide has five stages: define, request, review, verify and brief.

1. Define the Full Work Area

Start with more than the proposed trench, footing or basement line. Mark every area that may be affected by:

Excavators and attachments
Rock saws, augers and drilling equipment
Tippers and spoil trucks
Crane outriggers
Site sheds and temporary fencing
Stockpiles and loading zones
Temporary ramps and haul routes
Dewatering or drainage work

For projects involving utility trenching, map the entire service corridor rather than the first planned excavation area. Include connection points, crossings, pits, changes in direction and any area used by plant or delivery vehicles.

SafeWork NSW requires current underground essential-services information for the excavation area and relevant adjacent areas. This reflects the chance that machinery, supporting works and site access may place services at risk beyond the cut line.

2. Lodge the BYDA Enquiry Early

Submit the correct address, mapped work area, work type, dates and excavation details through BYDA. Its plan-request service provides access to information from participating asset owners.

Responses commonly arrive within minutes, but BYDA advises allowing up to two business days. The plans come from individual infrastructure owners rather than BYDA itself.

Build this response period into estimating and mobilisation. A late request may delay locating, consultation with asset owners, SWMS preparation and the planned start date.

3. Review Every Asset-Owner Response

The enquiry summary lists affected asset owners, contact details and expected response times. Check that every listed response has arrived before work starts.

For each response, record:

Asset owner
Plan issue date
Plan validity period
Service type
Conditions or permit requirements
Required locating method
Required exclusion area
Asset-owner contact details
Any supervision or attendance requirement

Expired plans require a new enquiry. A fresh request may be needed when the work area, scope or excavation dates change.

4. Add Other Site Records

BYDA may not capture every private or site-owned service. Review any available:

Survey and set-out drawings
Hydraulic and electrical drawings
Previous construction plans
Fire-service plans
Sewer diagrams
Stormwater plans
As-built drawings
Strata or facilities records
Demolition plans
Information supplied by the owner or occupier

This record check is valuable where excavation forms part of drainage stormwater works. Existing private drainage lines, abandoned pipes, old pits and undocumented connections may sit outside standard utility records.

5. Create a Controlled Site Pack

Keep the current plans, locator report, marked-up drawings, photographs, permits, SWMS and emergency contacts together. Make this information accessible to operators, supervisors and affected subcontractors.

Underground-services information must remain available for inspection during the work. SafeWork NSW guidance requires relevant information to be obtained before excavation starts and given to the people engaged to carry out the work.

Planning excavation, demolition or site clearing? Request a pre-excavation risk review before locking in plant, labour and mobilisation dates.

Site condition	Planning question	Likely method response
Narrow side access	Can the machine pass with safe clearance?	Use compact plant, remove obstructions, protect walls and fences
Steep driveway	Can plant travel safely under load?	Add ramping, spotters, staged spoil movement or craneable plant
Limited spoil route	Can spoil reach the truck without double handling?	Use conveyors, mini dumpers, bins or staged stockpiles
Rock present	What attachment is suitable for the space and noise limits?	Rock sawing, hammering or staged excavation method
Shared boundary	How will structures and neighbours be protected?	Dilapidation records, vibration controls, dust controls and clear sequencing
Overhead wires	Is plant or truck loading affected?	Adjust loading area, use spotters or consult service authority requirements

What Plans Never Tell You

Plans provide valuable asset information, but they are not permission to excavate mechanically up to a printed line.

BYDA states that plans indicate the presence of infrastructure rather than its exact location. Lines on a drawing may not confirm depth, alignment, material, condition or whether an asset has been altered since the drawing was prepared.

Possible plan gap	Required site response
Approximate alignment	Scan, mark and physically expose the service
Unknown depth	Pothole at crossing points and suitable intervals
Private service missing	Check owner records, visible features and local connections
Service altered after plan issue	Compare plans with pits, meters, valves and building entries
Abandoned service shown as active	Treat it as live until its status is confirmed
Several services grouped together	Expose each service and confirm its identity
Plan boundary near the work area	Extend the search area and contact the asset owner

Read the Physical Site

Plans should be checked against visible evidence. Look for:

Pits and access covers
Meters and connection boxes
Hydrants and valves
Marker posts
Warning signs
Conduits entering structures
Patched road or concrete surfaces
Changes in pavement or landscaping
Old structures that may retain live services

A mismatch between the plan and the site is a stop-and-review trigger. Do not choose the version that is easier for the programme.

Look Beyond Public Utilities

Private services may connect detached buildings, site sheds, pumps, pools, gates, lighting, irrigation systems or old structures. Temporary site services may cross access tracks or proposed excavation zones.

Speak with the owner, facilities manager, builder and relevant trades. Their information should guide further investigation, but it should not replace scanning or physical exposure where a service could affect the work.

Safe Potholing and Locating Sequence

Locating should move from broad information to physical proof. The following sequence forms a practical underground services checklist for active Sydney sites.

Step 1: Review and Mark the Plans

Overlay each asset response against the proposed excavation, survey set-out and plant routes. Mark expected service corridors on the ground using a clear system known by the crew.

Plan markings represent a warning zone. They are not confirmed asset positions.

Step 2: Scan the Work Area

Use a trained and competent locator where required by an asset owner, where records are unclear or where the service risk warrants it.

The SafeWork NSW Excavation Work Code identifies electromagnetic locating equipment and ground-penetrating radar as methods that may assist with service detection. The equipment must be used by people with suitable training and competence.

A scan may be affected by soil, rock, congested services, pipe material, signal interference and restricted access. Record the method, findings and limits in the locator report.

Step 3: Pothole to Confirm the Asset

Potholing exposes a small section of the asset so its horizontal position and depth can be checked.

Suitable approaches may include careful hand digging with suitable tools or vacuum excavation. The method should match the asset-owner instructions, ground conditions, service type and level of risk.

Sydney Water directs excavation teams to reconfirm service locations, inform workers about the hazards and excavate manually until relevant services have been located.

Potholes may be needed at:

Service crossings
Changes in direction
Entry points
Proposed footing or pier locations
Trench intersections
Areas where plans and scans disagree
Intervals needed to prove the service route

Step 4: Confirm Identity, Depth and Condition

Do not identify an asset through colour or appearance alone. Check it against plans, locating information, visible connections and asset-owner instructions.

Record:

Service type
Exposed location
Depth
Direction
Material
Condition
Clearance from the proposed excavation
Required support or protection

Photographs should include a scale or clear reference point. Mark-up drawings should use fixed site features rather than temporary stockpiles or equipment.

Step 5: Match the Plant to the Verified Conditions

Once service locations and ground conditions are known, review the plant, attachments and excavation method.

Good excavation equipment and fleet selection should account for:

Available working space
Required reach and dig depth
Machine weight and ground-bearing limits
Attachment size
Service clearances
Operator visibility
Spotter positions
Rock or hard-ground conditions
Noise and vibration restrictions
Safe loading and spoil-removal routes

SafeWork NSW states that plant used for excavation should be suitable for its intended task, kept in safe condition and operated by a competent person.

Step 6: Update the Work Method

Revise the SWMS, marked-up plan and excavation sequence using the verified findings. Set mechanical excavation limits, spotter duties, exclusion areas and emergency steps.

A SWMS must be site-specific when required for high-risk construction work. It needs to be accessible to workers and supervisors so they can follow the documented hazards, controls and work sequence.

Step 7: Conduct a Pre-Start Briefing

The supervisor should walk the work area with operators and affected subcontractors. Cover:

Verified service positions
Unverified zones
Excavation limits
Plant restrictions
Spotter locations
Asset-owner conditions
Stop-work triggers
Emergency contacts
Reporting lines

Repeat the briefing after a scope change, crew change, new plan response, weather event or unexpected site finding.

Send Rick Davis Contracting your site plans, proposed scope and target start date to request a pre-excavation risk review.

Delay and DamageScenarios

Utility strikes create costs far beyond the immediate repair.

A BYDA economic assessment reports more than 15,000 underground utility strikes each year across Australia. It estimates direct repair costs above $138 million and a total annual economic cost of $4.6 billion. Indirect and social costs were calculated at 32.4 times the direct repair cost.

SafeWork NSW found that 74% of the earthmoving plant and excavation incidents it reviewed resulted in serious injury or death. Plant contact with services was the most common incident group. One telecommunications asset owner reported 20,000 strikes in one year, linked to $20 million in annual damage.

Strike or discovery	Likely project effect	Main preventive action
Electrical cable contactite	Electric shock, burns, fire, shutdown and investigation	Current plans, locating, exposure and controlled clearances
Gas-service damage	Leak, fire risk, evacuation and emergency attendance	Asset-owner conditions, potholing and controlled excavation
Water-main strike	Flooding, erosion, unstable ground and property damage	Manual exposure and isolation planning
Sewer damage	Contamination, clean-up and work-area closure	Records review, locating and physical confirmation
Telecommunications strike	Service outage, repair cost and stakeholder complaints	Accurate marking, potholing and operator briefing
Unrecorded private service	Work stoppage, redesign and scope variation	Owner records, site inspection and locator review

Early coordination with experienced civil contractors can help project teams align service checks, site access, excavation sequencing, traffic movements and adjoining civil scopes before mobilisation.

Common Causes of Preventable Delays

Plans Were Requested Too Late

The project team receives asset-owner plans close to the planned start. Locating cannot be booked in time, the SWMS remains incomplete and plant mobilisation must be moved.

The BYDA Search Area Was Too Small

The request covers the excavation footprint but excludes the truck route, crane position or temporary drainage area. A new request is needed once the gap is identified.

A Plan Was Treated as an Exact Survey

The operator works from the printed line without potholing. The service sits at a different depth or follows an unexpected alignment.

Private Services Were Overlooked

Public utility plans are checked, but an owner-installed electrical cable, sewer branch or pump line crosses the work area.

The Scope Changed After the Briefing

A footing, pit or trench is moved without updating the service review. The revised excavation enters an area that was never located or exposed.

Findings Were Not Shared With the Operator

The estimator, locator or supervisor holds the latest information, but the operator receives an old drawing or a brief verbal instruction.

Underground Services Checklist

Use this checklist before excavation, demolition, boring, trenching, drilling, rock breaking or service installation begins.

Project Planning

Confirm the excavation footprint and adjacent work areas.
Mark plant, truck and material routes.
Lodge a BYDA enquiry using the full affected area.
Allow time for every asset owner to respond.
Check issue dates and expiry dates.
Review owner, survey, engineering and as-built records.
Identify private and temporary services.
Check overhead electrical-line risks for plant access.
Review approvals or conditions applying near water, sewer or stormwater assets.

Site Verification

Inspect pits, meters, valves, markers and service entries.
Compare physical evidence with supplied plans.
Engage a competent locator where needed.
Mark expected service corridors.
Pothole to confirm position and depth.
Record exposed services with measurements and photographs.
Resolve any conflict before mechanical work begins.

Work Controls

Update the risk assessment and SWMS.
Apply all asset-owner instructions.
Set mechanical excavation limits.
Nominate spotters and exclusion areas.
Protect or support exposed services.
Brief operators and subcontractors.
Keep current information accessible on site.
Set stop-work and emergency-response steps.
Review controls after changes to the scope or site conditions.

Contact Rick Davis Contracting for Underground Services in Sydney

Rick Davis Contracting has provided earthmoving services throughout Sydney for more than 47 years, working across excavation, demolition and civil contracting projects.

A pre-excavation review can identify gaps in the proposed scope, access plan, service information, plant selection and work sequence before they affect the programme.

Request a pre-excavation risk review from Rick Davis Contracting. Send the site address, proposed scope, available plans, survey, geotechnical report and target start date for an initial project assessment.

Frequently Asked Questions

What Is Before You Dig Australia?

BYDA is a national referral service that provides access to plans and safety information from participating infrastructure owners. The information may cover electricity, gas, water and telecommunications assets within a proposed work area.

Do BYDA Plans Show the Exact Location of a Service?

No. BYDA states that its plans indicate the presence of underground infrastructure rather than its exact location. Treat each plan as a guide and verify the asset through locating and physical exposure.

How Early Should a BYDA Enquiry Be Lodged?

BYDA advises allowing up to two business days for plans to arrive. Project teams need more time for plan review, late responses, locator bookings, potholing and work-method updates.

Do I Need a Locator After Receiving Plans?

A locator may be required by the asset owner or when plans and physical site features do not give enough certainty. Locating supports the investigation, but physical exposure may still be needed before nearby mechanical excavation.

What Happens When the Excavation Area Changes?

A new enquiry may be required when the mapped work area or scope changes. A fresh enquiry is required when the validity period of current plans has expired.

Who Must Obtain Underground-Service Information?

The person with management or control of the workplace must take reasonable steps to obtain current information about underground essential services in the excavation area. The information must be given to those carrying out the excavation work.

Can Excavation Start When One Asset-Owner Response Is Missing?

Work should not start in an affected area until the relevant plans and instructions have been received and reviewed. Contact the asset owner when a response is late or when its information requires clarification.

Is BYDA Enough for Private-Property Services?

BYDA may not identify every privately owned or site-installed service. Check records held by the owner, occupier, facilities manager, builder and relevant contractors, then verify the findings on site.