breaks

Interactive watershed break point delineation — a Shiny app for clicking stream networks to place break points, delineating upstream watersheds, and exporting sub-basins via pairwise subtraction.

Given a stream network and an area of interest, breaks lets you place points on streams, snap them to the FWA network, delineate the upstream watershed for each, and compute non-overlapping sub-basins by subtracting upstream catchments from downstream ones. Upload a CSV with extra columns — they’re preserved through snap and export.

Install

# install.packages("pak")
pak::pak("NewGraphEnvironment/breaks")

Quick Start

# Requires PostgreSQL with fwapg (via fresh)
# Set PG_*_SHARE env vars for database connection
breaks::run_app()

How It Works

1. Define AOI — three methods:

   • Type-ahead dropdown of BC watershed groups
   • Click the map to delineate an upstream watershed
   • Upload a GeoPackage or GeoJSON
   • Draw a polygon on the map

2. Place break points — click streams to place points (or upload a CSV with lon/lat columns). Each point snaps to the nearest FWA stream segment. Edit the name_basin column in the table to label each sub-basin.

3. Compute sub-basins — via fresh::frs_watershed_split(): delineate, sort by area, pairwise subtract, optionally clip to AOI.

4. Export — download break_points.csv (all columns preserved including name_basin) and subbasins.gpkg (EPSG:3005).

Requires

• PostgreSQL with fwapg (accessed via fresh)
• SSH tunnel or direct connection to the database
• PG_*_SHARE environment variables configured

Part of the Ecosystem

breaks is one piece of a larger watershed analysis workflow:

Package	Role
fresh	FWA-referenced spatial hydrology (data layer)
breaks	Delineate sub-basins from break points on stream networks
flooded	Delineate floodplain extents from DEMs and stream networks
drift	Track land cover change within floodplains over time
fly	Estimate airphoto footprints and select optimal coverage for a study area
diggs	Interactive explorer for fly airphoto selections (golem Shiny app)

Pipeline: fresh (network data) → breaks (sub-basins) → flooded (floodplains) → drift (land cover change).