PlaceDossier / BC places / Lakes

BC lake · 10 km² · Bowron watershed

Bowron Lake

Its median summer Secchi depth over 2016–2025 was 6.0 m, from 14 readings. Clearer than 69% of the 62 BC lakes with enough recent readings.

The readings

67 summer readings from open water on record from 1995 to 2025, at 3 sampling sites.

Median since 2012Compared with BC lakes
Secchi depth6.0 m
2016–2025, 14 readings
Clearer than 69% of the 62 BC lakes with enough recent readings.
Total phosphorus3.9 µg/L
2015–2025, 21 readings
Lower than 81% of the 100 BC lakes with enough recent readings (lower is clearer).
Chlorophyll a1.7 µg/L
2015–2025, 17 readings
Lower than 59% of the 83 BC lakes with enough recent readings (lower is clearer).
Secchi depth how deep a black-and-white disc stays visible: deeper means clearer water
02468 200020102020 2016: median 8.1 m from 1 reading2018: median 4.7 m from 2 readings2019: median 5.3 m from 2 readings2020: median 5.9 m from 1 reading2021: median 4.1 m from 2 readings2022: median 5.2 m from 2 readings2023: median 6.0 m from 2 readings2024: median 7.5 m from 1 reading2025: median 7.2 m from 1 readingm
Total phosphorus the nutrient that most often feeds algae in BC lakes
310 200020102020 1995: median 6.5 µg/L from 2 readings2006: median 3.5 µg/L from 4 readings2007: median 5.0 µg/L from 2 readings2008: median 14 µg/L from 4 readings2015: median 3.0 µg/L from 2 readings2016: median 3.5 µg/L from 6 readings2018: median 5.8 µg/L from 2 readings2019: median 5.1 µg/L from 2 readings2020: median 4.2 µg/L from 1 reading2021: median 4.1 µg/L from 2 readings2022: median 3.9 µg/L from 2 readings2023: median 17 µg/L from 2 readings2024: median 4.4 µg/L from 1 reading2025: median 5.4 µg/L from 1 readingµg/L
Chlorophyll a the green pigment in algae: a direct measure of how much is growing
0.313 200020102020 2006: median 2.0 µg/L from 1 reading2007: median 2.0 µg/L from 1 reading2008: median 1.3 µg/L from 1 reading2015: median 2.1 µg/L from 2 readings2016: median 1.9 µg/L from 2 readings2018: median 0.7 µg/L from 2 readings2019: median 1.6 µg/L from 2 readings2020: median 0.4 µg/L from 1 reading2021: median 1.9 µg/L from 2 readings2022: median 1.6 µg/L from 2 readings2023: median 2.3 µg/L from 2 readings2024: median 0.6 µg/L from 1 reading2025: median 1.7 µg/L from 1 readingµg/L

Median each year (bigger dot, more readings)Middle half of BC lakesBC median

Source: BC Environmental Monitoring Data System (EnMoDS) results, Environmental Monitoring and Analysis Branch, Province of BC, records to September 19, 2026 (Open Government Licence – British Columbia); lake outlines and names: Freshwater Atlas lakes, Province of BC (Open Government Licence – British Columbia). Summaries by PlaceDossier.

Nutrient level Inferred

Reads as oligotrophic (few nutrients, little algae, usually clear).

IndexClass
From secchi depth (6.0 m, 2016–2025)34oligotrophic
From total phosphorus (3.9 µg/L, 2015–2025)24oligotrophic
From chlorophyll a (1.7 µg/L, 2015–2025)36oligotrophic

Inferred by us, not a provincial classification. The index was built for summer readings from the middle of a lake; ours mix sites and months, so treat the class as a rough guide.

How we worked this out

Carlson's trophic state index (Carlson 1977, Limnology and Oceanography 22:361) turns each median into a score: 60 − 14.41 ln(Secchi m), 14.42 ln(phosphorus µg/L) + 4.15, 9.81 ln(chlorophyll µg/L) + 30.6. Classes after Carlson and Simpson (1996): under 40 oligotrophic, 40 to 50 mesotrophic, 50 to 70 eutrophic, 70 and over hypereutrophic.

Year by year

YearSecchi depthTotal phosphorusChlorophyll a
20257.2 m (1)5.4 µg/L (1)1.7 µg/L (1)
20247.5 m (1)4.4 µg/L (1)0.6 µg/L (1)
20236.0 m (2)17 µg/L (2)2.3 µg/L (2)
20225.2 m (2)3.9 µg/L (2)1.6 µg/L (2)
20214.1 m (2)4.1 µg/L (2)1.9 µg/L (2)
20205.9 m (1)4.2 µg/L (1)0.4 µg/L (1)
20195.3 m (2)5.1 µg/L (2)1.6 µg/L (2)
20184.7 m (2)5.8 µg/L (2)0.7 µg/L (2)
20168.1 m (1)3.5 µg/L (6)1.9 µg/L (2)
2015–3.0 µg/L (2)2.1 µg/L (2)
2008–14 µg/L (4)1.3 µg/L (1)
2007–5.0 µg/L (2)2.0 µg/L (1)
2006–3.5 µg/L (4)2.0 µg/L (1)
1995–6.5 µg/L (2)–

Median of each year's May to October readings; the number of readings is in brackets.

Source: BC Environmental Monitoring Data System (EnMoDS) results, Environmental Monitoring and Analysis Branch, Province of BC, records to September 19, 2026 (Open Government Licence – British Columbia); lake outlines and names: Freshwater Atlas lakes, Province of BC (Open Government Licence – British Columbia). Summaries by PlaceDossier.

Where it was sampled

  • E262699 Deepest point 61 readings
  • E221759 At centre 3 readings
  • E262704 East end 3 readings

Site names are tidied from the provincial records; the IDs find each site's full record there.

What this record doesn't cover

Algae bloom reports and invasive mussel checks aren't in this record: the province's Algae Watch map and mussel monitoring aren't published as open data. For swimming, check the regional health authority's beach advisories; for blooms and mussels, ask the province's regional environment office or the local lake association.

Readings are from the province's monitoring database: samples taken by provincial staff, volunteer lake monitors, and companies and local governments that sample under their permits. We keep the ice-free season (May to October), and for phosphorus and chlorophyll only samples from the top 5 m. We leave out sites whose names put them at a water intake, a sewage or industrial outfall, a mine or a permit holder's works, or on the shore (a beach, dock or boat launch): water there can differ a lot from the open lake. Each year's figure is the median of that year's readings. We give a lake a summary, a comparison with other lakes and a nutrient level only when it has at least 10 summer readings from open water, spread over at least 3 different years, since 2012; the summary is the median of those readings. With fewer, or only older ones, we show the readings and say there are too few to judge the lake. A reading below the lab's detection limit counts at that limit. One site can be a bay rather than the open lake, so a lake's figures can differ from one end to the other.

Water quality changes with the season, the weather and the part of the lake. These are past readings, not a test of the water today: before you buy, ask the local government and the lake association what's known, and test a drinking-water intake yourself.