PlaceDossier / BC places / Lakes

BC lake · 8 km² · Bowron watershed

Purden Lake

Too few readings to judge this lake: 45 summer readings from open water between 1986 and 2015, and we need at least 10 summer readings from open water, spread over at least 3 different years, since 2012 before we summarise or compare it. The readings are below.

The readings

45 summer readings from open water on record from 1986 to 2015, at 2 sampling sites.

Median since 2012Compared with BC lakes
Total phosphorusToo few readings to judge
2 readings since 2012, in 1 year
Too few readings to compare (2 readings since 2012, in 1 year).
Chlorophyll aToo few readings to judge
2 readings since 2012, in 1 year
Too few readings to compare (2 readings since 2012, in 1 year).
Total phosphorus the nutrient that most often feeds algae in BC lakes
310 199020002010 1986: median 12 µg/L from 1 reading1997: median 6.5 µg/L from 2 readings2004: median 6.0 µg/L from 11 readings2005: median 7.0 µg/L from 16 readings2006: median 2.0 µg/L from 11 readings2015: median 5.2 µg/L from 2 readingsµg/L
Chlorophyll a the green pigment in algae: a direct measure of how much is growing
13 199020002010 2015: median 3.2 µg/L from 2 readingsµg/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

Unclear: too few readings to judge this lake's nutrient level.

Left out for too few recent readings (we need at least 10 summer readings from open water, spread over at least 3 different years, since 2012): total phosphorus (2 readings since 2012, in 1 year); chlorophyll a (2 readings since 2012, in 1 year).

Year by year

YearTotal phosphorusChlorophyll a
20155.2 µg/L (2)3.2 µg/L (2)
20062.0 µg/L (11)–
20057.0 µg/L (16)–
20046.0 µg/L (11)–
19976.5 µg/L (2)–
198612 µg/L (1)–

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

  • E206651 Deep station 44 readings
  • E227179 Littoral site 1 reading

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.