Official Site of The State of New Jersey
The watershed boundaries used for the analysis by the Highlands Council are 14-digit Hydrologic Units (i.e., subwatersheds or HUC14s). There are 183 HUC14 subwatersheds that are located partially or entirely within the Highlands region.
A 1907 report by The Potable Water Commission of New Jersey noted the importance of the Highlands watersheds in its report explaining:
The Highlands watersheds are the best in the State in respect to ease of collection, in scantiness of population, with consequent absence of contamination; in elevation, giving opportunity for gravity delivery and in softness as shown by chemical analysis. These watersheds should be preserved from pollution at all hazards, for upon them the most populous portions of the State must depend for water supplies. There has been too much laxness in the past regarding this important matter.