HRWP Significant Groundwater Recharge Areas

Polygon file displaying significant groundwater recharge areas (SGRA) across the Toronto Region Source Protection Area (TRSPA) in the CTC Region.

The SGRA layer was developed to satisfy requirements of the Source Protection Plan for the Credit Valley, Toronto and Region and Central Lake Ontario region (CTC-SPC 2015) under the Clean Water Act (2006). Groundwater recharge occurs when rain/snow seeps down into an aquifer and generally this is associated with particular soil types (e.g., loose sand/gravel). SGRAs are delineated using a water budget modelling process, where the high potential recharge areas are delineated by the method outlined in full in CTC-SPC (2015). Details of the methodology used to develop this layer can be found in CTC-SPC (2015).

SGRAs have permeable soils such as sand or gravel that allow the water to soak easily into the ground. Under the Clean Water Act, 2006, a recharge area is considered significant when it helps maintain the water level in an aquifer that supplies drinking water (including private wells), and has higher than average recharge across the Source Protection Area. SGRAs are provided with vulnerable scores at the 2, 4 and 6 level. (Areas with a score of 2 are least vulnerable to contamination and areas with a score of 6 are most vulnerable).

This file was updated in 2018 and was approved as part of CTC's first Sec34 amendment in 2019.