PlaceDossier / BC places / Lakes

BC lake · 60 km² · Upper Shuswap watershed

Mabel Lake

Its median summer Secchi depth over 2016–2025 was 10.8 m, from 20 readings. Clearer than 93% of the 122 BC lakes with at least 5 readings.

The readings

306 summer readings on record from 1973 to 2025, at 2 sampling sites.

Median, latest 10 sampled yearsCompared with BC lakes
Secchi depth10.8 m
2016–2025, 20 readings		Clearer than 93% of the 122 BC lakes with at least 5 readings.
Total phosphorus2.9 µg/L
2016–2025, 20 readings		Lower than 95% of the 269 BC lakes with at least 5 readings (lower is clearer).
Chlorophyll a0.8 µg/L
2016–2025, 20 readings		Lower than 84% of the 156 BC lakes with at least 5 readings (lower is clearer).
Secchi depth how deep a black-and-white disc stays visible: deeper means clearer water
051015 19801990200020102020 1973: median 7.9 m from 2 readings1974: median 7.9 m from 2 readings1976: median 6.5 m from 6 readings1978: median 5.9 m from 6 readings1979: median 7.5 m from 4 readings1980: median 10.8 m from 2 readings1981: median 10.3 m from 2 readings1982: median 9.6 m from 6 readings1983: median 10.3 m from 2 readings1984: median 11 m from 3 readings1985: median 12.8 m from 2 readings1987: median 14.8 m from 1 reading1988: median 11.5 m from 1 reading1990: median 12 m from 1 reading1991: median 11.2 m from 2 readings1992: median 11 m from 2 readings1994: median 10.6 m from 2 readings1995: median 11.3 m from 2 readings1998: median 12.6 m from 2 readings1999: median 10.7 m from 3 readings2000: median 14.4 m from 2 readings2001: median 10.3 m from 3 readings2002: median 10.2 m from 2 readings2003: median 12.3 m from 2 readings2004: median 9.2 m from 2 readings2009: median 10.7 m from 2 readings2010: median 11.4 m from 2 readings2011: median 9.4 m from 2 readings2012: median 12.3 m from 2 readings2013: median 11.1 m from 2 readings2014: median 8.4 m from 2 readings2015: median 10.7 m from 2 readings2016: median 11.2 m from 2 readings2017: median 11.1 m from 2 readings2018: median 10.7 m from 2 readings2019: median 13.3 m from 2 readings2020: median 9.7 m from 2 readings2021: median 10 m from 2 readings2022: median 10.8 m from 2 readings2023: median 10.4 m from 2 readings2024: median 10.9 m from 2 readings2025: median 11.8 m from 2 readingsm
Total phosphorus the nutrient that most often feeds algae in BC lakes
310 19801990200020102020 1974: median 4.0 µg/L from 2 readings1976: median 4.0 µg/L from 6 readings1978: median 7.5 µg/L from 6 readings1979: median 6.5 µg/L from 4 readings1980: median 5.5 µg/L from 2 readings1981: median 5.0 µg/L from 2 readings1982: median 7.5 µg/L from 4 readings1983: median 10 µg/L from 2 readings1984: median 6.5 µg/L from 2 readings1985: median 5.5 µg/L from 2 readings1986: median 3.5 µg/L from 2 readings1987: median 3.0 µg/L from 2 readings1988: median 3.0 µg/L from 2 readings1989: median 5.5 µg/L from 2 readings1990: median 3.0 µg/L from 2 readings1991: median 3.0 µg/L from 2 readings1992: median 3.0 µg/L from 2 readings1993: median 3.0 µg/L from 1 reading1994: median 3.0 µg/L from 2 readings1995: median 3.5 µg/L from 2 readings1996: median 4.0 µg/L from 2 readings1998: median 4.0 µg/L from 2 readings1999: median 9.5 µg/L from 2 readings2000: median 3.5 µg/L from 2 readings2001: median 2.0 µg/L from 2 readings2002: median 3.0 µg/L from 2 readings2003: median 2.0 µg/L from 2 readings2004: median 2.0 µg/L from 2 readings2005: median 2.0 µg/L from 1 reading2006: median 2.0 µg/L from 2 readings2007: median 2.5 µg/L from 2 readings2008: median 4.5 µg/L from 2 readings2009: median 3.0 µg/L from 2 readings2010: median 4.0 µg/L from 2 readings2011: median 2.0 µg/L from 2 readings2012: median 2.9 µg/L from 2 readings2013: median 2.9 µg/L from 2 readings2014: median 4.5 µg/L from 2 readings2015: median 2.2 µg/L from 2 readings2016: median 2.4 µg/L from 2 readings2017: median 2.0 µg/L from 2 readings2018: median 2.7 µg/L from 2 readings2019: median 2.2 µg/L from 2 readings2020: median 3.3 µg/L from 2 readings2021: median 6.2 µg/L from 2 readings2022: median 3.8 µg/L from 2 readings2023: median 2.5 µg/L from 2 readings2024: median 3.5 µg/L from 2 readings2025: median 2.0 µg/L from 2 readingsµg/L
Chlorophyll a the green pigment in algae: a direct measure of how much is growing
13 19801990200020102020 1976: median 1.6 µg/L from 4 readings1978: median 0.9 µg/L from 4 readings1979: median 0.8 µg/L from 4 readings1980: median 0.9 µg/L from 2 readings1981: median 0.6 µg/L from 2 readings1982: median 1.0 µg/L from 4 readings1983: median 1.7 µg/L from 2 readings1984: median 1.6 µg/L from 2 readings1987: median 0.5 µg/L from 2 readings1988: median 1.1 µg/L from 2 readings1989: median 3.4 µg/L from 2 readings1990: median 1.2 µg/L from 2 readings1991: median 1.6 µg/L from 2 readings1992: median 1.6 µg/L from 2 readings1993: median 2.2 µg/L from 1 reading1994: median 1.2 µg/L from 2 readings1995: median 1.8 µg/L from 2 readings1996: median 1.7 µg/L from 2 readings1998: median 0.8 µg/L from 2 readings2000: median 1.0 µg/L from 2 readings2001: median 1.9 µg/L from 2 readings2002: median 1.7 µg/L from 2 readings2003: median 2.0 µg/L from 2 readings2004: median 1.6 µg/L from 2 readings2005: median 2.7 µg/L from 1 reading2006: median 1.4 µg/L from 2 readings2007: median 0.7 µg/L from 2 readings2008: median 0.8 µg/L from 2 readings2009: median 0.8 µg/L from 2 readings2010: median 0.8 µg/L from 2 readings2011: median 1.7 µg/L from 3 readings2012: median 1.7 µg/L from 2 readings2013: median 1.2 µg/L from 2 readings2014: median 1.9 µg/L from 2 readings2015: median 0.6 µg/L from 5 readings2016: median 1.3 µg/L from 2 readings2017: median 0.9 µg/L from 2 readings2018: median 1.2 µg/L from 2 readings2019: median 0.7 µg/L from 2 readings2020: median 1.4 µg/L from 2 readings2021: median 1.1 µg/L from 2 readings2022: median 0.8 µg/L from 2 readings2023: median 0.6 µg/L from 2 readings2024: median 0.6 µg/L from 2 readings2025: median 0.4 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

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

IndexClass
From secchi depth (10.8 m, 2016–2025)26oligotrophic
From total phosphorus (2.9 µg/L, 2016–2025)19oligotrophic
From chlorophyll a (0.8 µg/L, 2016–2025)28oligotrophic

Inferred by us, not a provincial classification. 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. 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.

Year by year

YearSecchi depthTotal phosphorusChlorophyll a
202511.8 m (2)2.0 µg/L (2)0.4 µg/L (2)
202410.9 m (2)3.5 µg/L (2)0.6 µg/L (2)
202310.4 m (2)2.5 µg/L (2)0.6 µg/L (2)
202210.8 m (2)3.8 µg/L (2)0.8 µg/L (2)
202110 m (2)6.2 µg/L (2)1.1 µg/L (2)
20209.7 m (2)3.3 µg/L (2)1.4 µg/L (2)
201913.3 m (2)2.2 µg/L (2)0.7 µg/L (2)
201810.7 m (2)2.7 µg/L (2)1.2 µg/L (2)
201711.1 m (2)2.0 µg/L (2)0.9 µg/L (2)
201611.2 m (2)2.4 µg/L (2)1.3 µg/L (2)
201510.7 m (2)2.2 µg/L (2)0.6 µg/L (5)
20148.4 m (2)4.5 µg/L (2)1.9 µg/L (2)
201311.1 m (2)2.9 µg/L (2)1.2 µg/L (2)
201212.3 m (2)2.9 µg/L (2)1.7 µg/L (2)
20119.4 m (2)2.0 µg/L (2)1.7 µg/L (3)
201011.4 m (2)4.0 µg/L (2)0.8 µg/L (2)
200910.7 m (2)3.0 µg/L (2)0.8 µg/L (2)
2008–4.5 µg/L (2)0.8 µg/L (2)
2007–2.5 µg/L (2)0.7 µg/L (2)
2006–2.0 µg/L (2)1.4 µg/L (2)
2005–2.0 µg/L (1)2.7 µg/L (1)
20049.2 m (2)2.0 µg/L (2)1.6 µg/L (2)
200312.3 m (2)2.0 µg/L (2)2.0 µg/L (2)
200210.2 m (2)3.0 µg/L (2)1.7 µg/L (2)
200110.3 m (3)2.0 µg/L (2)1.9 µg/L (2)
200014.4 m (2)3.5 µg/L (2)1.0 µg/L (2)
199910.7 m (3)9.5 µg/L (2)–
199812.6 m (2)4.0 µg/L (2)0.8 µg/L (2)
1996–4.0 µg/L (2)1.7 µg/L (2)
199511.3 m (2)3.5 µg/L (2)1.8 µg/L (2)
199410.6 m (2)3.0 µg/L (2)1.2 µg/L (2)
1993–3.0 µg/L (1)2.2 µg/L (1)
199211 m (2)3.0 µg/L (2)1.6 µg/L (2)
199111.2 m (2)3.0 µg/L (2)1.6 µg/L (2)
199012 m (1)3.0 µg/L (2)1.2 µg/L (2)
1989–5.5 µg/L (2)3.4 µg/L (2)
198811.5 m (1)3.0 µg/L (2)1.1 µg/L (2)
198714.8 m (1)3.0 µg/L (2)0.5 µg/L (2)
1986–3.5 µg/L (2)–
198512.8 m (2)5.5 µg/L (2)–
198411 m (3)6.5 µg/L (2)1.6 µg/L (2)
198310.3 m (2)10 µg/L (2)1.7 µg/L (2)
19829.6 m (6)7.5 µg/L (4)1.0 µg/L (4)
198110.3 m (2)5.0 µg/L (2)0.6 µg/L (2)
198010.8 m (2)5.5 µg/L (2)0.9 µg/L (2)
19797.5 m (4)6.5 µg/L (4)0.8 µg/L (4)
19785.9 m (6)7.5 µg/L (6)0.9 µg/L (4)
19766.5 m (6)4.0 µg/L (6)1.6 µg/L (4)
19747.9 m (2)4.0 µg/L (2)–
19737.9 m (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

  • 0500118 MABEL L @ SOUTH END (PE00173) 271 readings
  • 0500117 MABEL L @ TSUIUS CREEK 259 readings

Site names and IDs are as recorded in the provincial database; 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. Each year's figure is the median of that year's readings; the summary is the median of every reading in the lake's latest 10 sampled years. 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.