Precipitation Monitoring

Weekly precipitation samples are collected on a weekly basis from monitoring equipment in Southampton, PEI on a year-round basis. The precipitation that is collected includes rainwater and snow, often called wet precipitation. The main objective of the sampling is to monitor changes of precipitation quality over time, specifically pH.  Acid rain can be measured using the pH of wet precipitation, with normal rain having a pH of about 5.6. Acid rain usually has a pH of between 4.2 and 4.4.*     

* source:

What is the pH of precipitation on PEI?

The pH of the collected samples varies from year to year, and results are available since 1982. The graph below shows the average annual pH values of the precipitation samples. No samples were collected in 2014, 2015 and 2016. A summary of the average annual pH values is available for download.


Graph showing annual average of pH for rainwater samples
Image caption: 
Annual average of pH for rainwater samples

What other data are available?

Although pH is the focus of the precipitation monitoring, several other parameters are also collected and analyzed. The full dataset from 2004 to present is available for download in the province's Open Data Portal

Who can I contact for more information?

Sean Ledgerwood (Water and Air Monitoring Supervisor)
4th Floor, Jones Building
11 Kent Street
Charlottetown, PEI C1A 7N8
Telephone: (902) 368-4686
Fax: (902) 368-5830



Published date: 
April 19, 2021
Environment, Energy and Climate Action

General Inquiries

Department of Environment, Energy and Climate Action
4th Floor, Jones Building
11 Kent Street
PO Box 2000
Charlottetown, PE C1A 7N8

Phone: 902-368-5044
Toll-free: 1-866-368-5044
Fax: 902-368-5830
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