Weekly water quality science at four sites across Halifax's inner harbour. All data free and public.
Six parameters at each of our four monitoring sites, updated automatically from our public data log.
Each parameter is a different lens on the same question: is this water healthy, and what is putting pressure on it? Together they tell us far more than any single reading could.
Warmer water holds less oxygen and speeds up algae growth. It sets the baseline that every other reading has to be interpreted against, and flags heat stress on marine life.
Rising temperatures are an early warning of climate and runoff stress.
How acidic or basic the water is. Healthy harbour water sits in a narrow band; swings signal pollution, acid rain, or runoff, and even small shifts can harm shellfish and fish eggs.
A stable pH is one of the clearest signs of a balanced ecosystem.
A direct fingerprint of sewage, fertilizer, and wastewater. Even in small amounts it is toxic to fish, so any reading above zero points straight at a pollution source nearby.
The most immediate indicator of wastewater and runoff contamination.
The end product of nutrient pollution. High nitrates fuel algae blooms that choke out oxygen. This is the parameter Atlantic watershed groups track most closely for nutrient loading.
Reveals long-term nutrient buildup from urban and agricultural runoff.
The unstable middle step as ammonia breaks down into nitrates. A spike means pollution is fresh and actively being processed, so it times exactly when contamination entered the water.
Pinpoints recent pollution events, not just long-term averages.
Ammonia, nitrites, and nitrates form a timeline of pollution as it breaks down. Paired with pH and temperature, they let us tell fresh contamination apart from long-term nutrient loading, at each site, every week.
Trend lines over time for every parameter across all four sites, straight from our master data log.
Every reading we take goes straight into a public log anyone can view, download, and build on. No paywalls, no sign-ups, no exceptions.
No one was publishing this data. We changed that.
From a swimming lake to the open Atlantic, each site tells a different part of the harbour's story.
Site 01Recreational swimming site on Halifax's urban shoreline. Monitored weekly for the parameters that determine whether it is safe to swim.
"Thousands of Halifax residents swim here every summer with no public water quality information available."
Site 02Urban freshwater–saltwater interface receiving direct stormwater runoff from Dartmouth's street network.
"This site consistently shows the highest pollutant readings in our network, a direct window into what urban runoff does to harbour water."
Site 03Open ocean exposure with strong tidal flushing provides a natural baseline for comparison against urban sites.
"Our cleanest site shows what Halifax Harbour water looks like without urban pressure, essential context for interpreting all other readings."
Site 04The heart of Halifax Harbour near Pier 21 captures the combined effects of port activity, boat traffic, and urban runoff at the city's most iconic waterfront.
"The most visible and recognizable site in our network. Monitoring here connects our science to the harbour Halifax knows best."
All four monitoring locations across the inner harbour.
"Halifax had no publicly accessible, community-led water quality monitoring for its inner harbour. We built it."
Halifax Harbour is the centre of the city's identity. People swim in it, fish from it, and live beside it, yet week to week there was no public record of what was actually in the water. Swimmers at Chocolate Lake, residents along Dartmouth Cove, and anyone curious about the waterfront had no accessible, current water quality information to turn to.
So we built the missing piece: a registered non-profit society running weekly sampling at four sites across the inner harbour, measuring six parameters each visit, and publishing every reading to a free public dashboard the same week it's collected.
We are youth-led and Halifax-based, founded in June 2026. We do this because it's our harbour too, and because good decisions about it start with good, open data.
Our data doesn't stop at this website. We follow the same open, standardized methods used across Atlantic Canada so our readings can be compared, combined, and built on by researchers, watershed groups, and government.
The free, open-access hub for water quality data across Atlantic Canada, holding nearly 70 years of monitoring records. Publishing our readings here puts them alongside government and university datasets.
Explore the platform →A hub connecting community-based water monitors across the region with training, standardized protocols, and equipment. The backbone that keeps citizen-science data credible and comparable.
See their resources →Established Nova Scotia groups monitoring harbours, lakes, and beaches under the Atlantic Coastal Action Program. Models for community-led stewardship, and natural collaborators as we grow.
Learn more →Universities like Dalhousie and Saint Mary's run harbour and geography research programs. Open, consistent local data like ours is exactly what student and faculty projects look for as a starting point.
A pathway we're actively pursuingThe harbour belongs to everyone. There are three ways to be part of keeping watch over it.
We are always looking for site leads and volunteer samplers across Halifax.
Express interestWe welcome partnerships with schools, universities, and environmental organizations.
Get in touchOur dashboard updates every week. Follow us on Instagram for weekly readings and findings.
Follow @halifaxharbourwatchReadings, field notes, and what they mean, posted every week from the shoreline.
Halifax Harbour Watch Society is a registered Nova Scotia non-profit society. All data is open access and free forever.