What causes high turbidity?
High turbidity is generally a result of soil erosion in the catchment. Turbidity readings are best done during high flows when erosion is most likely to be occurring. Why is turbidity not good? Soil erosion in itself is serious. However, a turbid water body could also be low in oxygen due to decreased light penetration, and therefore lowered photosynthetic activity in the water column. Turbid water in a running stream could also have a scouring effect, washing aquatic organisms off the rocks, therefore physically decreasing biological levels in the water body.
