Planetscope sensors observe in wavelength regions that allow for retrieval of the turbidity of water in both inland and coastal waters.
Several spectral indices have proved useful for the retrieval and mapping of chlorophyll a levels in inland waters, with this being indicative of algal biomass.
The high temporal frequency of planetscope observations allows for regular monitoring of water levels (e.g., in reservoirs) by combining water extent and bathymetric information, allows water depth to be routinely estimated.
Pollution is often manifested in changes in water colour or different impacts (e.g., increased algal blooms as a result of higher nutrient loads).
Septic tanks and slurry pits can leak, with this causing waste discharge into soils which increases nutrients and potential plant productivity or dieback (e.g., of grasses).
These can be caused by increased rainfall but these are often small and difficult to detect from even high resolution sensors. Erosion from areas affected lead to changes in water quality, turbidity and colour. The impacts can extend downstream.