Intensive farming is being blamed for high nitrate levels in drinking water in the Canterbury region.

In catchments with high nitrate levels, they would be required to take immediate action to reduce excessive leaching.

Canterbury dairy farmers are trialling injecting freshwater back into aquifiers in a part of the plains with high nitrate levels.

(2) By treating the fibrous cellulose nitrates with liquid solvents of the high nitrate diluted with non-solvent liquids, and more especially water.