The paper presents results of studies on ground and surface water pollution from two liquid manure handling objects: a lagoon and a 700 ha area of medium and heavy soils fertilised annually with liquid manure from the pig farm. The studies showed elution of mineral soluble components, mostly nitrates, sodium and potassium, to ground waters. The effect of these objects on water quality was insignificant and did not change water quality as compared with non-fertilised areas.