The City of Guelph’s Water Supply Master Plan (2006) recommended reviewing the feasibility of returning to service a number of wells that had not been used for several years, including the Clythe, Sacco and Smallfield wells. These wells were shut down due to poor water quality, declining production and/or increasing maintenance requirements.
The City undertook this project to determine the long term production capability and water quality available from each of these wells. Work included geophysical logging, flow profiling and video inspections to characterize all wells. The data collected using these technologies, when examined in conjunction with one another, allow the identification of water producing features and other areas of interest. The zones identified during this preliminary testing were necessary in the development of a discrete zone sampling program to help identify the zones producing the poor quality water.
Following the completion of a 3 day pumping test at the Clythe well, the project focus shifted to determining the feasibility of installing liners in the Sacco & Smallfield wells to seal off the contaminant producing zones and improve water quality. This was achieved by installing inflatable packers and temporary liners in both the Sacco and Smallfield wells to simulate permanent liner installations. Once these temporary measures were in place, a 13 day pumping test was conducted at Smallfield, with the Sacco well pumped concurrently over the last 7 days of the test. During these tests, samples were collected daily by Lotowater staff for water quality analysis. This regular sampling was used in the short term to determine if the isolated zone and the production interval were hydraulically connected.
If deemed suitable for return to municipal service, the findings of this work will be used in subsequent studies to identify any necessary treatment requirements for these wells.
To-date, all activities that have been undertaken by Lotowater have been completed on budget and within the time frame and schedule outlined by the client.