swmm-canada · git:20260808.d071884 · 2026-08-08 · sha256 adcc25fa80e3b2f3

swmm-canada git:20260808.d071884A

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---
name: swmm-canada
description: Fetch a ready-to-run SWMM model for any Canadian area from the SWMMCanada upstream service — real published municipal storm pipes where a supported city covers the AOI, synthesized elsewhere in Canada. Input is a bbox or GeoJSON polygon plus a rainfall date window. Use for Canadian locations; outside Canada route to swmm-anywhere instead. Documentation contract only — the runtime tool is the in-process fetch_swmm_from_canada; there is no script or MCP server in this skill.
---

# swmm-canada

**Fetch a ready-to-run SWMM model for a Canadian area from the SWMMCanada upstream service, then run, audit, calibrate, and force it in one canonical run folder.**

Use for any AOI inside Canada. The service auto-selects the build mode: **real published municipal storm networks** where a supported city covers the AOI (35 cities at the 2026-08 sync, e.g. Victoria, Ottawa, Toronto, Calgary, Vancouver, Regina), **synthesized** anywhere else in the country. Outside Canada, route to `swmm-anywhere` (global, synthesized).

This skill is a documentation contract: the implementation is the in-process typed tool `fetch_swmm_from_canada` (a pure-stdlib HTTP client, ADR-0001). There is no script directory and no MCP server here, and that is deliberate — the service boundary is HTTP, and the tool is already on the runtime's golden path.

## What this skill does

Given an AOI (bbox `[min_lon, min_lat, max_lon, max_lat]` or a GeoJSON Polygon string) and a rainfall date window (`start_date`, `end_date`, ISO dates):

1. **Announces a preview** (best effort): which mode and city the service will use.
2. **Submits the build** to the SWMMCanada tasks API and polls with live progress (network fetch, subcatchments, DEM, landcover/soil, climate, build).
3. **Downloads the model bundle** and lands it in the canonical layout (ADR-0004): `model.inp` in `05_builder/`, the full `swmm_model.zip` (including the service's own `validation.json`) in the opaque `10_upstream/swmmcanada/` box.
4. **Returns** the INP path, run directory, service URL, task id, build mode, and the upstream validation record.

Validated live end to end: a downtown Victoria AOI produced a real 423-subcatchment network in 173 s, ran under the local `swmm5` unmodified, and audited cleanly; the whole fetch-run-audit chain took 178 s.

## Required inputs

- `aoi_geojson` (GeoJSON Polygon string) **or** `bbox` (four WGS84 floats).
- `start_date`, `end_date`: the rainfall window (`YYYY-MM-DD`). This decides which observed rainfall the service attaches, so changing the window changes the storm.

## Optional inputs

- `run_dir`: reuse an existing run directory (otherwise a timestamped `runs/agent/swmm-canada-*` is created).
- `infiltration`: `CURVE_NUMBER` (service default), `HORTON`, or `GREEN_AMPT`; passed through verbatim.
- `base_url`: override the service endpoint for one call.

## Configuration

The service URL comes from the `AISWMM_SWMMCANADA_URL` environment variable (a local container at `http://localhost:8000` or a hosted backend). `aiswmm doctor` probes `GET /api/v1/healthz` when the variable is set and reports reachability; unset is a quiet OK because the upstream is optional.

## What to do next (the chain)

Pass the returned `run_dir` and `inp_path` forward so every stage lands in the same run folder:

1. `run_swmm_inp` (agent) or `aiswmm run --inp <inp> --run-dir <run_dir>` (CLI) — simulate.
2. `audit_run` / `aiswmm audit --run-dir <run_dir>` — provenance, QA verdict, diagnostics.
3. `aiswmm calibrate` with observed flow data — the fetched model is an **uncalibrated first-pass estimate**; expect the audit gate to flag routing continuity on raw builds, which is the gate doing its job.
4. `run_climate_scenarios` / `aiswmm climate --params-json best_params.json --patch-map <map>` — precipitation-scaled what-ifs on the calibrated model.

## Boundaries

- **Outside Canada**: the tool fails soft with a hint before any HTTP round trip; use `swmm-anywhere`.
- **Real network vs synthesized**: decided server-side per AOI; the result reports which mode ran. Treat both like the synth path for QA purposes (reference-free checks until calibration).
- **Provenance**: aiswmm never re-derives what the service already recorded; the zip in `10_upstream/swmmcanada/` is the durable upstream artifact, with the service URL and task id as foreign keys.