Lac McArthur (EHEZQ) is in Val-des-Monts, Les Collines-de-l'Outaouais, Quebec, at 45°42′29″N 75°40′13″W / 45.7080555°N 75.6702778°W / 45.7080555; -75.6702778.

[5][6] Water quality measurements were taken in mid-June, July and August 2015.

[2] Average total phosphorus concentration was 4.4 μg/L, so the lake is classed as oligotrophic, or poor in nutrients.

[7] The average concentration of chlorophyll in the lake was 1.50 μg/L, which indicates that the biomass of microscopic algae suspended in water is low and confirms the oligotrophic classification.

[8] The average concentration of dissolved organic carbon in the lake was relatively low at 2.98 mg/L.