The Ontario Lake and River Routing Product (OLRRP) is a high-resolution, vector-based lake-river routing GIS product over the Province of Ontario. The OLRRP supplies network topology and various subbasin, channel, and lake attributes required for hydrological modelling. Version 2 of OLLRP is an enhancement relative to Version 1. Key upgrades in OLLRPv2 include using the Provincial Digital Elevation Model to derive elevation related attributes, almost 500 non-HYDAT hydrometric stations and over 200 hydropower generating station locations are now defined as Points of Interest (POI), an improved POI snapping procedure improves the inclusion rate and accuracy of POI on the lake and river networks and an enhanced suite of cloud-based Python GIS post-processing tools (BasinMaker) are now available for users to access and customize their case study routing networks. See the OLLRPv2 website: https://uwaterloo-olrrp.shinyapps.io/OLRRP-V2/.

The OLRRPv2 connects together 245,576 subbasins (average area 4.3 km²) and
82,928 lakes (surface areas ranging from 0.1 km² to 4,506 km²) and assigns 4033 POI to these subbasins and lakes. The agreement between ECCC HYDAT reported drainage areas (998 in total) and the corresponding OLRRPv2 computed drainage areas is excellent. For 74% of comparisons, drainage areas show less that a 2% difference while in only 4% of these comparisons, the absolute drainage area difference exceeds 10%. The OLLRPv2 provides detailed routing networks for any of the above lakes/subbasins/POIs and thus supports semi-distributed hydrological modelling, vector-based routing only modelling and other water resources analyses requiring the connectivity of lakes and rivers in Ontario.