manure and run off. that can be a large issue. use to have nightmare neighbor/farmer. and would allow manure to physically get so bad, that it would create its own "creak of manure" that would run across his property into ditches and into creeks.
contact your local state agriculture department. "ron settles" from ag department, dealt a lot with here in Illinois over the years with the nightmare neighbor/farmer. if you can show that the water quality is out of specifications / past what is allowed by law. and/or manure handling is not properly being dealt with. the local ag department should be able to help clear the issues up, and will take water samples and like. to point of fining person, to other court resolutions.
many times not having say gutters, down spots, making sure rain water does not mix in with the manure and cause bigger mess can be resolved easily, other times collection area for manure is not taken care of so all run off water from rain also goes into the area causing larger mess.
BUT, for your own damage, fish kills and like. you would most likely need to sue the person to get anything back. you can not force another person to do something, but get cash to fix issues on your side, and damages you may have incurred.
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look at aeration systems. it is not the small little misty bubbles that are important, or water shooting up from your pond in a fountain. but rather the "water current" throughout your pond. generally a large vortex current (swirling around) pond can help bring more water to the surface of the pond were more gas exchange can happen.
granted some aeration systems do provide more of a donuts shape water current. were air stones being the center. but most folks ponds/lakes are shallow compared to surface area of there ponds/lakes. and being able to create a larger swirling / vortex / whirl pool like water current more likely more beneficial to to them.
this can be done with "air lifts", DIY style fairly easily. it is just learning curve of how to build an air lift bank, and then physical cost of pump and plumbing pieces, and then the air line put in between pump and air lifts.
aeration systems, help off gas and bring in dissolved oxygen into the water. this can help promote more bacteria to break down fish waste and decaying vegetation. and help reduce food sources for annoying vegetation. also helps get more oxygen to the fish.
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if you can not deal with issues from cattle farm at the source and water coming from them passes the laws/regulations.
aeration system is first choice possibly for me. but perhaps building a smaller pond and turning it more into a filter pond. were you can physically treat the water before coming into your pond. this could be dwell time (how long it takes water to flow through the filter pond), to aeration, to promoting water vegetation growth to help act like filtration media to help clean the water to other.
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google your address and then click up on maps, click on the "satellite/earth" icon to switch from roads to greenry. and you can get a better view of things.
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most water vegetation only grows from 4 feet or shallower waters. (sun light not able to penetrate any deeper than approx 4 feet deep)
if you walk out into pond to go swimming, and sinking up to your knees in black smelly dirt. you have a large food source for vegitation. aeration system more likely help reduce the depth (thickness layer) of the black dirt under the water.
