List what needs to reach each destination
Start with the destination rather than drawing the shortest line across the lawn. A shed may need power and communications, a pool equipment area may need several connections, and a drainage project has its own outlet requirements. Ask each relevant trade to identify the starting point, destination and any intermediate access points. Mark these against the same property plan. If one trade is working from an old shed position and another from the revised position, the apparent efficiency of a shared excavation disappears before the machine arrives.
Describe how you intend to use the destination. For a workshop in Cranbourne, discuss the planned equipment with the electrician; for a Berwick pool, have the pool builder coordinate the equipment layout with the service trades. You do not need to specify cable sizes or pipe arrangements yourself. You need the responsible trades to provide excavation instructions that can be compared. Include future provisions only where a trade has assessed them. An unidentified spare pipe buried because it might be useful later can be difficult for the next owner or contractor to interpret.
Distinguish the new route from existing services
A proposed route does not establish what is already underground. Give the contractor any property records you have and identify visible items such as meters, pits and inspection points. Ask who obtains the service information, arranges relevant on-site locating and resolves discrepancies. Before You Dig Australia’s guidance sets out planning, preparation, physical verification and protection before proceeding. Receiving plans is one part of that process, not permission to assume every asset is located precisely.
Private garden wiring, irrigation or earlier alterations may need additional investigation through the appropriate trade. Tell the contractor about work you know was done, while distinguishing recollection from an actual record. If something appears during excavation that is not understood, leave identification and response to the responsible people. The WorkSafe and Energy Safe guide to underground services addresses the risks of ground penetration where services may exist. Do not ask the operator to treat an unfamiliar pipe or cable as abandoned because it looks old.
Ask the trades whether sharing is feasible
A shared route is an option for the trades to assess, not a default trench detail. Different services can have requirements concerning separation, depth, support, protection and accessibility. Ask each trade to review the combined proposal and provide the excavation dimensions and sequence they require. Avoid averaging conflicting instructions or choosing the shallowest request to reduce digging. If the arrangement cannot be reconciled, separate routes or staged work may be the sensible outcome.
Bring the trades into the same conversation before pricing is finalised. A simple marked plan and written notes may be enough for an initial coordination discussion, while the project may require more detailed design documents before construction. Ask who produces the final instruction the excavator follows. That document should distinguish shared lengths, separate branches and locations needing special attention. An email saying “use the same trench as the plumber” is incomplete if the plumber has not reviewed the electrical route or the equipment entry points.
Resolve crossings before opening the full run
Look for where the proposed services cross existing paths, driveways, garden walls or other services. These points often need more coordination than the long open section of lawn. Ask the trades to identify what must remain, whether any disconnection is needed and how the work will be staged. Photograph surfaces that will be disturbed and describe the intended reinstatement. If access to the house depends on crossing the work area, have the contractor plan a safe alternative rather than leaving residents to improvise.
A trench route near a boundary or easement also needs the relevant project checks. The excavation contractor should receive the approved route, not be asked to decide whether an easement restriction can be ignored for a short distance. For council drainage involvement, use the City of Casey’s easement guidance as a starting point for the appropriate enquiry. Identify whose approval or design input is needed before the affected section is scheduled. A clear hold on one location is easier to manage than reopening a completed route.
Confirm drainage from the outlet back to the project
Drainage needs a resolved destination and design, not simply a trench toward the street. Ask the plumber which outlet is proposed, what information confirms it and whether the route can meet the project requirements. The excavator should work to the relevant instructions for that system. Do not substitute a neighbour’s arrangement or a visible kerb opening for confirmation of the appropriate connection. If a drainage decision is still pending, keep it visibly unresolved in the excavation brief.
The City of Casey’s LPOD guidance notes that council drain details are a guide and do not describe the property’s internal downpipe network. Ask the plumber what must be verified on site. If a new shed or pool equipment area changes the drainage arrangement, resolve that alongside the other service routes. The easiest line to excavate may not be the line the drainage design needs, so settle this before treating the proposed shared route as final.
Fix building entries before concrete or paving covers them
The last part of a service run can be the most awkward to change. Ask where each service enters the shed, equipment enclosure or other destination, and how that location relates to doors, posts, benches and equipment. Have the relevant trades coordinate penetrations and sleeves with the slab or building designer. A route can be satisfactory across the yard but arrive at the wrong side of a fixed structure. Catching that on a drawing is simpler than addressing it after concrete or paving has been placed.
Mark any future access points and keep them clear in the landscape plan. Ask which covers, valves or other items need to remain accessible after the surface is finished. Give that information to the landscaper as well as the excavator. If you want the final area to look uncluttered, discuss the layout before installation rather than requesting that useful access points be buried or hidden afterwards. The homeowner’s aesthetic preferences can be accommodated only within the requirements of the installed systems.
Programme installation, inspection and backfill together
Ask each trade what must happen while its work remains exposed. The programme should identify installation, testing, inspection where required, record-taking and release for backfill. The Building and Plumbing Commission’s drain inspection guidance explains obligations associated with below-ground sanitary drainage. Have the licensed plumber explain the requirements for your particular work and the timing the excavation contractor must allow. Do not assume every drainage task has the same process.
Agree how the excavator receives permission to backfill. A named person and a written message are clearer than “everyone looked happy when they left”. If several trades use parts of the route, mark which sections are released and which must remain available. A completed electrical installation does not automatically release a nearby plumbing section. Keep the site-control arrangement in place during the gap, with access managed by the contractor. Nobody should enter or alter the trench simply to speed up a booking or make the yard look finished.
Match reinstatement to what will cover the trench
Tell the contractor what surface will ultimately cover each part of the route. Lawn, a garden bed, paving and a vehicle area have different handover expectations. Ask the responsible designer or trade what backfill and preparation the surface requires, and ensure the excavation quote includes that specified work or names the contractor who will complete it. A single line saying “backfill included” may leave the final surface preparation undefined.
Separate rough closure from final reinstatement in the programme. Some surfaces may be finished later by a landscaper or concreter, while other areas need to be safely usable when the excavation contractor leaves. Identify any retained material, imported product or later trim explicitly. If another trade will disturb the area again, avoid paying for a final finish that must immediately be removed. At the same time, agree how the area is managed during the interval; an unfinished construction surface should not be casually presented as normal household access.
Record what was installed before it disappears
Ask the trades what as-installed records they provide and agree how the records will relate to the property. Photographs are more useful when labelled with location, direction and stage, and when the relevant trade explains what they show. A set of close-up pictures without reference points can be hard to interpret years later. Keep the final route information with the drawings, certificates and invoices rather than leaving it in an expiring message thread or on a contractor’s phone.
Records should reflect changes made during the work. If a route moved around an obstruction or an entry point changed, ask for the final arrangement to be recorded before the area is closed. Future contractors will still need appropriate locating and safety checks; your file is useful background rather than permission to dig from memory. This distinction helps a homeowner provide better information for later fencing, landscaping or repair work without assuming that an old sketch shows every service that may now exist.
Compare the excavation scope against every trade’s scope
Before accepting a quotation, trace the work from locating existing services to final reinstatement. Identify who supplies bedding or other specified materials, who installs services, who arranges inspections, who approves backfill and who finishes the surface. Ask about waiting time or return visits if the trades cannot attend in the same sequence. A low excavation total may be reasonable for a tightly defined task, but it should not be mistaken for a complete multi-trade installation.
Use the checklist below to prepare the unresolved questions for your contractors. For an established Narre Warren garden, existing services and occupied-house access may dominate the discussion. For a new shed, entry locations and the slab programme may matter most. Give Casey Earthworks the agreed excavation requirements and the relevant trade contacts so the quote can address the actual job. The most useful outcome is a coordinated scope in which every section can be installed, checked and closed at the correct point.