The United States Geological Survey maintains many stream gauges along the West Branch Delaware River. The station by the Village of Delhi, in operation since 1937, but making daily measurements since November 1996, is located upstream from the bridge on Route 28, and upstream from the confluence of the Little Delaware River. This station had a maximum discharge of about and a gauge height of from floodmark on January 19, 1996 and a maximum gage height of on August 28, 2011 as Hurricane Irene passed through the area. It had minimum discharge of on September 25, 1964 and a minimum gauge height of on September 16–17, 2016. The Hobart station, in service since 2000, located upstream from Maple Street in the Hamlet of Hobart. This station had a maximum discharge of about and a gauge height of on August 28, 2011 caused by Hurricane Irene. It had minimum discharge of on November 13, 2001 and November 19, 2001. The Walton station, in service since 1950, located downstream from West Brook in the Village of Walton. This station had a maximum discharge of about and a gauge height of on June 28, 2006 during the 2006 Mid-Atlantic United States flood. It had minimum discharge of on September 15 and November 22, 1964. The Hale Eddy station, in service since 1912, located upstream from the confluence of East and West Branches. Since the construction of the Cannonsville Reseevoir this station had a maximum discharge of and a gauge height of on June 28, 2006 during the 2006 Mid-Atlantic United States flood. It had minimum discharge of on October 20, 1963. The maximum discharge, prior to construction of Cannonsville Reservoir in 1963, was on March 22, 1948. Outside the period of record: In the flood of October 10, 1903 this station reached a discharge of roughly
Fishing
The West Branch is tailwater fishery. This means the same cold water releases that keep it cooler in the summer, keep the river a little warmer in the winter and early spring. The upper section can be cleaner than other rivers during periods of heavy runoff. During high water on the Cannonsville Reservoir, many bait fish spill over the dam. These factors all provide and excellent environment for trout to thrive in. The trout population in this river is naturally reproducing, during the warm months stocked trout from smaller and warmer tributaries will seek sanctuary in its cool water. The West Branch Delaware River was divided into two sections when the Cannonsville Reservoir was formed. Downstream of the Cannonsville Reservoir, there are large numbered wild populations of brown trout and rainbow trout and an occasional brook trout can be caught although none are stocked. Seasonal anadromous runs of american shad with reports of occasional striped bass. This section is considered one of the bestfly fishing trout streams in the United States, due to the cold water released from the reservoir.