1 leg · 1 level · W, FB, P, SR
Single-leg, single-level water-corridor viaduct. Carries water pipe, power line, service rail, and fibre. Self-building deployment off the MMC-VA main aqueduct — the workhorse of the Sovereign Aqueduct Network capture programme.
MMC-VD is the lightest design in the MMC viaduct family. A single pylon leg — built from the same P#7 modular precast concrete column segments as every other MMC pylon, but in a single-leg configuration — supports a single-level deck carrying four services: a water pipe (the primary load, diameter project-specific), a power line (to feed pumping infrastructure at source and any in-line boosters), a service rail (for inspection, maintenance, and supply movement during operations — also the construction mechanism), and fibre optic cable (for SCADA, leak detection, valve control, and security monitoring). No freight, no maglev, no HVDC. The structure is single-purpose, sized for water and its supporting services. Cost per kilometre is the lowest in the MMC structure catalogue.
The strategic role of MMC-VD is set by the geometry of the Sovereign Aqueduct Network. The continental capture programme captures monsoon water from multiple distributed river catchments; each catchment needs its own conduit reaching from the MMC-VA continental trunk into the source. The fingers extending from the main corridor on the aqueduct network maps are MMC-VD deployments. Aggregate length across the continental programme is expected to be 1,500–3,000 km.
Per-kilometre cost is engineered for a 10 m average foundation depth — the baseline assumption applied across all MMC structure cost pages. Deeper foundations (river crossings, floodplain) add cost in proportion to the additional drilling depth; the per-pylon foundation cost line item below scales accordingly.
Per-kilometre cost is split into three layers: Structure (the bare elevated platform — foundation, pylon, cap beam, deck, walkway), Services (service-specific equipment installed on the structure — service rail base, power supports, fibre wireway), and Install (all field labour and plant). Total per km is the sum of the three. The service items themselves (water pipe, power conductor, fibre cable) are catalogued separately on the relevant Service pages and added to deployment cost.
The bare elevated platform — foundation, pylon, tubular tension element, transverse cap beam, platform deck, and permanent equipment (walkway, handrails, fall protection). Per-km basis: 40 pylons at 25 m spacing, 40 deck spans, 1 caisson per pylon at 10 m baseline depth. Module costs are Megafactory pour rate + Hub and die allocation at moderate platform utilisation (~$310/module). Pre-feasibility grade, ±30%.
| Item | Per pylon / span (AUD) | Per-km (AUD) |
|---|---|---|
| Cutter head (sacrificial hybrid) — high-chrome steel + hardened inserts, stays in ground as PT anchor | $10,000 | $400,000 |
| Caisson ring segments (precast concrete) — 4 m OD, 300 mm wall, 1 m tall, C65, 10 rings per caisson | $6,850 | $274,000 |
| Caisson anchor cap (precast concrete) — 4 m OD annular cap, 1 per caisson | $935 | $37,400 |
| Pressure grout — annular grouting, rock socket bond, water seal | $600 | $24,000 |
| Tubular tension element — 7″ × 29 ppf L80 13Cr API 5CT, ~12 m per pylon at ~$280/m delivered | $3,360 | $134,400 |
| Pylon column segments (precast concrete) — tapered P#7, 2 segments per pylon for 8 m height | $1,520 | $60,800 |
| Transverse cap beam (precast concrete) — runs perpendicular to corridor axis, 1 per pylon | $1,210 | $48,400 |
| Platform deck modules (precast concrete) — 25 m span, 1 per span, integrated saddles via P#7 rib | $1,010 / span | $40,400 |
| Walkway, handrails, fall protection (galvanised steel) — permanent platform equipment | $5,000 / span | $200,000 |
| Structure subtotal | $30,485 / pylon | $1,219,400 |
Service-specific equipment installed on the structure to enable the four services MMC-VD carries: service rail (inspection, supply, construction mechanism), power line supports, and fibre wireway. The service items themselves (water pipe, power conductor, fibre cable) are catalogued separately on the relevant Service pages and added to deployment cost.
| Item | Per span (AUD) | Per-km (AUD) |
|---|---|---|
| Service rail base and ties — rail base mounted to deck, includes rail materials | $3,750 | $150,000 |
| Power line supports / insulators — bracketry for HV power feeder to pumping infrastructure | $1,200 | $48,000 |
| Fibre wireway / conduit — tray and conduit for SCADA, leak detection, security monitoring | $800 | $32,000 |
| Services subtotal | $5,750 / span | $230,000 |
All field labour and plant required to deploy the structure and services. Drilling rig service charged at ~$1,200/hour all-in (crew + plant + fuel); per-pylon allocation assumes 6 hours/caisson at 10 m baseline. The self-building methodology compresses install cost: the rig and crane work from the deck of the already-built section, no road access required to each pylon, service rail laid behind the rig becomes rolling stock for the next cycle.
| Item | Per pylon / span (AUD) | Per-km (AUD) |
|---|---|---|
| Foundation drilling service (rig hours, crew, fuel; 10 m baseline, ~6 hrs/caisson) | $7,200 | $288,000 |
| Pylon segment erection (P#7 module stacking, tubular running, post-tensioning at cap) | $2,500 | $100,000 |
| Transverse cap beam and deck module placement | $1,500 / span | $60,000 |
| Service rail laying (materials + labour per 25 m span) | $3,000 / span | $120,000 |
| Power line, fibre, conduit pull (per span) | $1,500 / span | $60,000 |
| QA, commissioning, sign-off (allocated per pylon) | $800 | $32,000 |
| Install subtotal | $16,500 / pylon | $660,000 |
Structure + Services + Install. The service items themselves (water pipe, power conductor, fibre cable) are catalogued on their respective Service pages and added to deployment cost. Foundation costed at 10 m baseline depth; deeper foundations on river crossings or floodplain sections add cost in proportion.
Pre-feasibility grade, ±30%. Modules costed at Megafactory pour rates from Memo 2 (Megafactory Economics) plus moderate-utilisation Hub and die allocation (~$310/module). Install rates are pre-feasibility benchmarks against light civil construction at corridor scale. All figures AUD. Detailed engineering and quantity surveying required before any binding use.
Two factors materially shift the per-kilometre cost of MMC-VD deployment: