Concession Road to 8th Concession Road as a Local Improvement under this new policy”.

The resolution was not part of the recommendations proposed by Administration and resulted from requests from residents about repurposing septic tanks for rainwater storage for irrigation or stormwater management purposes. As directed, Administration undertook research to prepare a policy that would allow for this reuse. In doing so, however, it became evident that the challenges and requirements that would accompany such a policy would be significant, and it became necessary to return to Council for direction.

Discussion:

Rainwater harvesting is the practice of collecting rainwater to reuse and/or as a storm water management strategy for an individual property. The practice of rainwater harvesting and distribution is regulated in the Province of Ontario by legislation, including the Ontario Building Code (OBC) and Ontario Electrical Safety Code (ESA), as well as technical standards maintained by the Canada Safety Association (CSA) and National Sanitation Foundation (NSF). In some locations where rainwater harvesting is being used for storm water management, local conservation authorities such as the Essex Region Conservation Authority (ERCA) may also have regulatory jurisdiction.

In the Province of Ontario, rainwater can be collected and used for grey water recycling (to flush toilets or urinals) and sub-surface irrigation (O.Reg 350/06, Articles 7.1.5.3.(2) & 7.7.1.1.& 7.7.3.2, CSA Standard B128.1 and NSF Protocol P151). Stored rainwater cannot be used in sprinkler applications due to the possibility of bacteria or algae in an airborne mist that could be inhaled by people or animals. All rainwater collection systems must be designed by a licensed professional engineer to address the unique technical and site requirements associated with designing and installing a rainwater collection system for an individual property per the Ontario Building Code Act Chapter 23, Article 15.9 (3). Rainwater collection systems must include a pre-filter and a post-filter mechanism, as well as an overflow system, which typically rely on an electric pump inside of the reservoir tank. In Ontario, rainwater management systems must be designed to be cold resistant (insulation and/or a heating system) or be decommissioned in the winter to prevent the damage associated with freeze-thaw cycles.

Challenges with Using Repurposed Septic Tanks for Rainwater Storage:

Septic tanks are designed to contain and manage household wastewater, including human waste. Usually constructed from reinforced concrete or polycarbonate plastic, septic tanks consist of one or more chambers that collect wastewater and hold it so that solids can settle and separate from liquid components. Inside the tank, anaerobic bacteria decompose solids to slow the rate of buildup. Decomposition alone is often not enough to keep a tank adequately free of solids to work properly; therefore, a periodic cleanout maintenance is required. As a result of the hazards associated with the contents of a septic tank, periodic maintenance and inspection of residential tanks is