Oct. 7, 2019 – Several changes are in the works for drinking water protection zones and chemical storage rules in the Mississippi-Rideau Source Protection Region.
Under Ontario’s Clean Water Act, municipal drinking water sources such as lakes, rivers and wells are protected from contamination through a combination of intake and wellhead protection zones, rules for chemical use and other threats, and risk management plans for landowners whose activities pose a risk to drinking water supplies.
There are two proposed amendments to the Mississippi-Rideau Source Protection Plan and Assessment Report under Section 34 of the Clean Water Act.
1. North Grenville municipal well:
In 2015, a new municipal well was constructed in Kemptville in the Municipality of North Grenville. The proposed amendment will bring the well under the same Clean Water Act protections as the region’s 13 other municipal systems, as required by law. The amendment will include revised Wellhead Protection Area (WHPA) mapping for North Grenville and the Village of Merrickville-Wolford (groundwater flow to the Merrickville-Wolford system is affected by pumping at the new well in Kemptville.)
The updated maps could affect landowners if they engage in certain activities that pose potentially significant drinking water threats. In these cases, risk management staff will work with the owners to manage the threats through custom risk management plans.
2. Chemical policy revision:
The Source Protection Committee also wants to tweak its rules regarding Dense Non-Aqueous Phase Liquids (DNAPLs) – industrial chemicals that are denser than water. If spilled, they tend to sink into the ground and even in small amounts can contaminate the deepest groundwater sources.
Currently, any businesses established after Jan. 1, 2015 which store or handle DNAPLs are banned in areas where they could pose a significant drinking water threat, specifically in Intake Protection Zone-1 and Wellhead Protection Areas A, B and C. For some municipalities, the affected area can be quite large.
When developing risk management policies for DNAPLs, the committee expected to find these chemicals only in large quantities (i.e. industrial drums) at dry cleaning or manufacturing facilities. But after completing detailed background research and site visits, the committee realized DNAPL chemicals can also be found in small quantities, particularly in auto repair shops (i.e. chlorinated brake cleaner in aerosol cans).
With such large prohibition zones in some parts of the region, the restrictions could create unnecessary barriers for small business development in the future. The committee has proposed an amendment to make life a bit easier for small businesses in these zones, while still ensuring drinking water is protected.
Under the new policy, storage and handling of any amount of DNAPLs within areas of the highest vulnerability (score of 10) will remain prohibited. But the storage and handling of DNAPLs in quantities of less than 25 liters within WHPA B and C (scores 4 to 8) will now be permitted, if accompanied by a risk management plan. Storing or using large quantities of DNAPLs (more than 25 liters) within WHPA B and C will be banned.
Retail stores selling unopened containers are exempt from these rules, except for areas with the highest vulnerability.
How to view the amendments:
The proposed amendments are available on the Mississippi-Rideau Source Protection Region website at www.mrsourcewater.ca/en/public-consultation.
They can also be viewed in person at:
- Mississippi Valley Conservation Authority, 10970 Hwy. 7 Carleton Place, ON (8 am – 4 pm)
- Rideau Valley Conservation Authority, 3889 Rideau Valley Drive, Manotick, ON (8:30 am – 4:30 pm)
Residents and business owners are invited to provide written comments before Nov. 7, 2019.
For more information or to provide comments, please contact:
Mississippi-Rideau Source Protection Region
613-692-3571, ext. 1148.
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