Configure a validated, low-carbon stone arch bridge online and download the drawings.
Learn more Engineer sign inBuild up to four times more bridges than reinforced concrete. Local materials and labour save 60–80% on comparable spans.
No steel and only a fraction of the cement of concrete bridges — avoiding 50–75% of construction-related carbon emissions.
A technology proven over millennia. Stone arches still in service today carry modern heavy traffic loads.
Natural stone and low arch profiles settle into river valleys instead of imposing on them — bridges that weather, gather moss and grow more beautiful with age.
A worked example — the four steps every vada project follows, from the field survey to the finished crossing.


A simple level survey of the river cross-section — banks, bed and water levels — is entered into vada.


Set the arch type, span and number of arches on the surveyed section. vada returns the 3D model and the full construction drawing set.


The same design carries its bill of quantities — stone, cement and earthworks — ready for local pricing, procurement and tendering.


Masons build straight from the drawings using local stone, sand and cement — a crossing that carries traffic for generations.
Reference crossings built under the Enabel/SAKiRP programme, Kigoma, Tanzania.
vada is available to licensed engineers, who design and issue each pack under their own registration as engineer of record. Sign in or request access to be set up.
vada is for qualified engineers. Accounts are provisioned by Bernage rather than self-served: you sign in, design your crossings, and issue drawing packs under your own name and professional registration as the engineer of record. To be set up, request access.
For each crossing: a live 3D model, an indicative bill of quantities, and a full construction drawing set — overview, elevations, longitudinal and cross sections, foundation and excavation plans, a river cross-section sheet, and a grouped bill of quantities. Every issue is versioned, and revisions are tracked.
Arch type (Roman or segmental), span, number of arches, deck width, foundation depth, wing walls and road approaches — all fitted to the river cross-section you survey, with live hydraulics showing the waterway opening against the required flood section.
vada builds standard configurations whose geometry and quantities come from a design basis (the SABA standard, derived from the Enabel manual) that is validated two ways: exactly against the reference design model, and against 45 stone-arch structures built under Enabel in Tanzania. Configurations outside the standard range are flagged for manual engineering rather than issued automatically.
You are, as the engineer of record. vada is a computational design aid — it applies standard tables and geometry and does not perform site-specific verification. Hydrology, flood and scour assessment, geotechnical and foundation design, loading and any code checks remain your responsibility, and you review and approve each design (applying any seal your jurisdiction requires) before it is issued. This is confirmed at every generation and set out in the Terms of Service.
Licensing terms and pricing are being finalised during the pilot. Get in touch below and we will set you up.
Tell us about your project. We reply within two working days.