That question is my investigative problem . I am just wondering what investigative project can i done with my problem which is "How is a water supply affected by run off from nearby dairy farms?".. please help me in kinda confused on this. Thanks robet_lim@yahoo.com:

Runoff from dairy farms not only includes bacteria from cow droppings but can also include items such as phosphates and other minerals that can have negative effects. As far as how it effects the water, the cow droppings can carry e-coli bacteria (which will cause severe intestinal problems in humans), the phosphates/misc minerals can encourage growth of water organisms that will choke out the waters natural oxegen content. Those are the 2 main big issues w/dairy farm runoff. It makes the water purification process more challenging because there are more bacteria in the water, more suspended solids, etc. All that requires the addition of more chemicals and disinfectants. And the water filters must be backwashed more frequently, which slows down water production. The final water quality isn't affected much - there are rules about how clean the water must be - but getting it clean becomes a chore. A really good way to research this topic would be to take a tour of a water plant! I used to work around fresh water plants. They pretty quiet during most of the day so it wouldn't be hard to arrange a tour and learn about it first hand. Other solution is keeping the runoff and then irrigate them to Grass Field: