Site tools
The 3 tools that gather what Swiss public registers know about a plot.
Before opening a norm, an engineer opens four browser tabs: the cantonal geological register, the polluted-sites cadastre, the natural-hazard maps, the federal geoportal. These three tools make that round for them and return the result dated, attributed, and split between what is settled and what is not.
This is not a geotechnical study. It is a survey of public registers. No design value — friction angle, bearing capacity, modulus — follows from a geological description served here. An agent that produced one would have produced a plausible and wrong number; the methodology forbids it explicitly.
scan_site
Starts the survey around a Swiss address and returns the site id.
dossierIdstringrequiredReturned by open_dossier or list_dossiers. One site per dossier: open
the project's dossier first.
addressstringrequiredThe address as the user writes it: "Av. de Rhodanie 58, Lausanne".
radiusnumberHow far to look for boreholes and constraints, in metres. From 50 to 500, 300 by default.
The address is geocoded server-side against swisstopo, and any coordinates you supply are ignored. A model that has seen a lot of Swiss maps will happily produce plausible LV95 numbers; a site placed two hundred metres off returns the neighbouring parcel's boreholes without a single call failing.
The scan runs in the background and takes a few seconds. Returns
{ siteId, dossierId, label, east, north, radius, next }.
get_site_context
Reads what the scan found, grouped by topic, each value with its source and the date the data was current — not the date it was read.
siteIdstringrequiredReturned by scan_site.
Returns two separate lists:
| Field | What it holds |
|---|---|
established | what the registers settled: municipality, parcel, elevation, geological unit, lithology, boreholes, seismic zone, aquifer |
unresolved | what they did not settle, with the reason for each point |
boreholes | how many, how many have strata read, the distance to the nearest |
notice | the reminder that these facts are not a study |
Report unresolved to the user in full. "No borehole within three hundred
metres, molasse likely but unconfirmed, budget for three drillings" is the
sentence that sets the price of a bid. An agent that reads only the first list
presents the fiche as complete, which it almost never is.
Each unresolved point carries its kind:
indicative— a value exists, but its own source warns it is not precise enough. That is the case of the ground-class maps, "to be considered as indicative maps, not precise at parcel level".uncovered— no automatic source covers this point and a step has to be taken. Snow load, wind and underground networks are in this case.
get_boreholes
Reads the boreholes the scan found, nearest first, with their logged strata. This is the call
that answers "what is the ground actually made of here" — get_site_context only says how many
boreholes there are.
siteIdstringrequiredReturned by scan_site.
limitnumberHow many to return, nearest first. 1 to 40, 8 by default. total always says
how many the radius holds, so a short list never reads as an empty
neighbourhood.
withStrataOnlybooleanKeep only the boreholes whose strata were read. A cantonal register publishes the log of roughly two boreholes out of three.
Each borehole carries its distance from the site, its depth, the year it was drilled, its
layers (depth interval, description, period), the SIA 261 ground class logged in that hole
when the canton publishes it, the water table when it was measured, and the links to the
cantonal documents — the drilling log, the site plan.
One borehole is one observation, at one point, on one day. Quote it with its distance. Never interpolate a layer between two boreholes: that is an interpretation, and it belongs to an engineer, not to a machine. Never derive a design value — friction angle, bearing capacity, modulus — from a layer description.
The documents are links, never files. The canton of Vaud forbids redistributing its structured data to third parties; hosting its PDFs would go further than calling its API. Give the link.
What the survey looks up
| Topic | Sources |
|---|---|
| Situation | swisstopo: municipality, EGRID parcel, elevation from the terrain model |
| Ground | GeoCover at the point and over the neighbourhood, cantonal borehole register with strata, water table measured in a piezometer, modelled bedrock top |
| Constraints | polluted sites, groundwater protection, natural hazards, noise sensitivity, zoning, distance to forest |
| SIA 261 actions | seismic zone, ground class |
The ground class has four sources and the tool picks the best available: the class observed in a nearby borehole first — the canton of Vaud publishes one on roughly two boreholes out of three — then the cantonal polygon, then the local spectral microzonation, and last the federal map, which still refers to the 2003 edition of the norm and says so.
Boreholes stay with their canton. Vaud forbids redistributing its structured data to third parties: it is read for your project, attached to it, and never shared between organisations. The original documents — borehole log, site plan — are linked, never copied to us.