Because surface water is exposed to more contaminants from the environment, than underground water.
The Earth's water reservoirs from largest to smallest: Ocean Polar ice and Glaciers Groundwater Freshwater Lakes Saline Lakes Soil Moisture Atmosphere Rivers
Hydrosphere
Hydrosphere
Without rivers and or lakes, life cannot be supported. Without water, there would be absolutely no life on Earth.
in the underground and rivers, streams ,lakes.
Groundwater is in the ground, not in lakes or rivers.
groundwater has more freshwater than rivers and lakes
lakes and rivers
Ice, rivers, lakes, and groundwater are all sources of freshwater
The hydrosphere.
fresh groundwater
lakes and rivers and groundwater (underground)
Groundwater
Lakes,Rivers,Atmosphere, and Groundwater.
Ocean,ice,rivers,lakes,groundwater
Groundwater percolates into aquifers underground, where it can be stored for long periods of time or flow into rivers, lakes, and oceans. Runoff typically flows into streams, rivers, lakes, and eventually reaches the ocean.
Oceans, Ice, Rivers and Lakes, and Groundwater.