Watch for #WinterWednesdays posts about how to manage snow storage and salt application and storage to reduce risk to drinking water sources.
Snow ploughed from roads and parking lots can be contaminated with road salt, oil, grease and heavy metals from vehicles, litter, and airborne pollutants.
When the snow melts, these contaminants are released and can enter nearby surface water and groundwater creating a threat to drinking water sources.
Snow, therefore, must be stored and disposed of in an appropriate manner. Storing large quantities of snow in one location concentrates the contaminants in melt water, which results in a greater impact on the surrounding water, soil, and habitat.
If the storage area is large, a significant release of chemicals to groundwater or surface water can occur.
These include sodium and chloride from road salt.
To learn more about how you can help to manage salt and snow threat activities download this guide:
This is a 4 MB (very large-sized) PDF file of the Good Practices for Winter Maintenance in Salt Vulnerable Areas guide.
Also, download our local Salt and Snow fact sheet (2015):
This is a 300 kb (medium-sized) PDF file of a two-page fact sheet about drinking water threats from snow and salt activities.
Parking Lot Design Guidelines
When parking lots are designed with winter maintenance in mind, they require less salt application to maintain the same level of service without increasing liability.
Using only the amount of salt that is needed in parking lots can help to mitigate anticipated chloride increases in local watercourses.
A number of partner agencies have developed Parking Lot Design Guidelines to Promote Salt Reduction.
These guidelines include design features, site plans, template municipal policies, and next steps intended for use by designers, regulatory agencies, owners, contractors, and others.
To find out more visit the Lake Simcoe Region Conservation Authority’s web page on Parking Lot Design Guidelines:
- Parking Lot Design Guidelines (Web page)
- Fact Sheet – Parking Lot Guidelines (LSRCA) (PDF file)
- Parking Lot Design Guidelines – Full Report (LSRCA) (PDF file)
- Municipal Policy Template (LSRCA) (PDF file)
Drinking water threat activities from road salt storage; road salt application; and snow storage
Road salt storage; road salt application; and snow storage are three activities, of a total of 22 activities, that pose potential threats to the safety and quality of our municipal drinking water sources.
We need your help to protect our local water supply from these threats.
Understanding the threat
Storage of snow:
Snow removed from roads and parking lots may be contaminated with salt, oil, grease and heavy metals. Storing large amounts of snow in one area concentrates the contaminants. Once the snow melts, these contaminants may reach groundwater or surface water. This poses a threat to drinking water sources.
Under Ontario’s Clean Water Act, 2006 storage of snow in a wellhead protection area is a significant threat only where:
a) The storage area, below grade, is larger than 0.01 hectares, or;
b) The storage area, above grade, is larger than 1 hectare.
No existing significant threats for snow storage have been identified in the Maitland Valley or Ausable Bayfield source protection areas.
Salt storage and application:
Road salt is a tool to maintain safe roads but it has the potential to affect human health if it reaches sources of drinking water. Salt storage and application are considered a significant threat in wellhead protection areas when:
a) Salt storage is greater than 5,000 tonnes, or
b) Salt is applied where the impervious (for example paved) surface is greater than 80 per cent
(The above circumstances, as of 2020, are subject to change)
No existing significant threats for salt storage or application have been identified in the Maitland Valley or Ausable Bayfield source protection areas.
Will plans affect me?
Policies in the local source protection plans do not require actions on all properties that store salt or snow. Only in areas where this threat is considered to be significant is it required to comply with the policies. However, we encourage you to find out more about best management practices for reducing the impacts of snow and salt activities. (For more information, download or ask for the fact sheet on vulnerability, threats, and risks.)
Where could salt and snow pose a significant threat?
On properties located within 100 metres of the municipal well (Wellhead Protection Area A), or in the two-year time-of-travel zone (Wellhead Protection Area B) where the vulnerability score is 10.
For maps showing vulnerable areas, go to our website at sourcewaterinfo.on.ca or contact staff of your source protection region.
No existing significant threats for snow or salt have been identified for this region. To learn more about protecting drinking water, please contact your local risk management official or staff of the source protection region.
Examples of threat activities
Activities that pose threat to drinking water sources include:
- Septic systems; On-site sewage
- Fuel oil (including home heating oil)
- Liquid fuel such as gas stations
- Chemicals (toxic chemicals such as organic solvents and dense non-aqueous phase liquids or DNAPLs)
- Commercial fertilizer
- Pesticides
- Nutrients (manure, bio-solids, grazing)
- Waste disposal sites (including storage of hazardous waste)
- Sewage works (sewage treatment plants, municipal sewers)
- Road salt and snow storage
- Others: For the list of 22 provincially prescribed drinking water threats, go to this web page:
Drinking water threat activities in Ontario
How are road salt and snow storage threats being addressed?
Local source protection plans use a variety of tools to protect municipal drinking water sources:
Storage of snow:
Prohibition
Any new snow storage will be prohibited only where it poses a significant threat.
Restricted Land Use
This is a ‘flag’ that helps municipalities identify properties where snow storage could require a risk management plan or could be prohibited.
Storage, handling and application of salt:
Education and Outreach
Staff in this region are reaching out to people like you in order to let you know how you can help to protect local drinking water sources.
Restricted Land Use
This is a ‘flag’ that helps municipalities identify properties where the activity requires a risk management plan or is prohibited.
Strategic Action
Where salt storage is a low or moderate threat the municipality will ask commercial landowners to develop salt management plans.
Find out more online:
- Plans and maps
- Province of Ontario
- Winter tips
- Smart About Salt Program
- Guidelines on Snow Disposal and De-icing Operations in Ontario
Contact us:
Ausable Bayfield Maitland Valley Source Protection Region
c/o 71108 Morrison Line, RR 3 Exeter, ON • N0M 1S5
1–888–286–2610 • sourcewaterinfo.on.ca
Maitland Valley Source Protection Area: 519-335-3557 Ausable Bayfield Source Protection Area: 519-235-2610
This project has received funding support from the Government of Ontario. Such support does not indicate endorsement of the contents of this material.
The content provided in this publication is intended for local educational and information purposes only.
Every effort has been made to ensure the correctness of information as at the publication date (November 2020).
Subject to change.
For legislation and regulations visit ontario.ca
The storage of snow is considered a drinking water threat under Ontario’s Clean Water Act, 2006.
There are 22 activities which can pose threats to our drinking water sources.
These include:
- Waste disposal sites
- On-site sewage systems (including septic systems)
- Sewage works (sewage treatment plants, municipal sewers)
- Fuel oil (including residential heating oil)
Liquid fuel - Nutrients (manure, bio-solids, outdoor livestock areas)
- Commercial fertilizer
- Pesticides
- Road salt
- Snow storage
- Chemicals including toxic chemicals such as organic solvents and dense non-aqueous phase liquids (DNAPLs)
- Aquaculture
Snow storage is considered to be a significant drinking water threat in many vulnerable areas surrounding municipal wells, called wellhead protection areas (WHPAs), and areas surrounding surface water intakes in areas called intake protection zones (IPZs).
How are threats from snow storage being addressed?
For information on how salt and snow storage are addressed please review the source protection plans for the Maitland Valley and Ausable Bayfield source protection areas.
