The stream rises out of a swamp between the Wyanokie Crest and Buck Mountain. It is characterized by a meandering path, broken up by several decent waterfalls including Otter Hole and the impressive Chikahoki Falls.
Looking at the area topography, there may be evidence of stream capture. Blue Mine Brook and a tributary of West Brook seem to be slowly eroding toward each other and may eventually meet with Posts Brook or one another. The result would be an act of stream piracy, wherein the runoff from one stream is captured from another, effectively cutting off the water supply from the unlucky stream. Without knowing more details, it's hard to say which is capturing which.
Downstream, the first major waterfall is Otter Hole. It is the namesake of Otterhole Rd, and "OH Parking" is the second most popular trailhead in Norvin Green State Forest. Several unnamed cascades are located downstream from Otter Hole. Most of these require bushwhacks. The stream levels out before it passes the yellow Wyanokie Crest trail, which is a complicated stream crossing during high water.
After receiving its most significant tributary off the slopes of Carris Hill, the stream begins to lose elevation again, passing a wider waterfall that's vivid and loud with increased flow. But the most striking cascade lies just ahead.
Named for after a Lenape word meaning "turkey lands", the 30-foot Chikahoki Falls is Posts Brook's greatest asset. Its flow rate is highly variable, from a barely-visible trickle to a roaring whitewater double cascade. It can serve as a indicator of drought or moisture surplus in the Wyanokie Region. The waterhole's shoreline similarly fluctuates between a smaller pool and inaccessibly flooded.
Below Chikahoki, the stream flattens out and flows towards the town of Wanaque, NJ. It passes by a spur that runs off into the Wanaque Reservoir through a gorge.
It briefly merges with Blue Mine Brook to form Lake Iosco. An eastern outlet continues as Posts Brook into Rainbow Lake, flowing beside part of Doty Rd. Finally, Posts Brook closely follows Ringwood Avenue as the South Twin Lake before it crosses under the street through a culvert. It merges into the Wanaque River approximately 6.75 miles from its source.
Though this waterway is short and partially protected from access by the NJDWSC, it contains a gorge with several cascades. It rises out of the Rockburn Springs of Long Swamp Mountain. Exiting out of the Long Swamp itself, it makes contact with West Brook Road just east of Otterhole Road's terminus. Not many cascades can be found here, but this area of the Brook can be accessed from Black Rock parking at Kiwanis Campground Road. It continues east past a tributary that receives water from the Kitchell Lake dam. Another tributary follows right behind, with water from the dammed Boy Scout Lake in Camp Wyanokie. From here, the West Brook reaches its gorge, containing several cascades of photographic interest.
After the gorge, the Brook enters Wanaque Reservoir watershed property that is strictly protected against trespassing by NJDWSC patrol and security cameras. West Brook continues past a farm after which it receives water from the Burnt Meadow Brook. It quickly empties into the Wanaque Reservoir thereafter.
Once named "Long Pond River", the Wanaque River’s primary source is the Long Pond itself -- modern day Greenwood Lake. It also receives volume from the watershed of New York's Sterling Forest, starting with the confluence with Jennings Brook. Past Jennings, Wanaque flows over several small cascades towards a gorge called the Mine Hole. The centerpiece of the gorge is Hewitt Falls, a raging cascade in any season. The force of these falls powered the Long Pond Ironworks in its heyday, with the ruins of hydroelectric waterwheels located just downstream. The shape of the waterhole's basin, combined with the power of Hewitt Falls' flow rate, creates a whirlpool in a cove to the left of the cascade in high water. Unfortunately this may have contributed to the death of a swimmer in 2016. The Mine Hole has been closed to swimming ever since the fatality.
After the Mine Hole, the river flows past the Long Pond Ironworks itself. Now a ghost town, it was a booming plantation that once produced 14% of the world's iron product. It flourished until being forced into bankruptcy by more sophisticated operations near the Pennsylvania Coal Fields. Production of charcoal -- necessary to operate the Ironworks’ furnaces -- required so much wood that nearby Ramapo hills were completely stripped bare of tree cover. In the century since the Ironworks ceased to operate, the forests have made a strong recovery.
Past the Ironworks, additional water is brought in from Sterling Forest in the form of the Beech Brook, which meets the Wanaque River at the head of the Monksville Reservoir. Constructed in 1980s to relieve drought concerns, the reservoir is located on top of the old town of Monksville, which was submerged upon the creation of the dam. Most houses were demolished while two houses of historical significance were relocated. Monksville is known for its fishing and boating. It is a secondary part of North Jersey's water supply, supporting the Wanaque Reservoir and feeding it when necessary.
Monksville Reservoir is held in by the Monksville (or Stonetown) Dam, completed in 1987. Immediately after the dam, the Wanaque River reappears as the massive Wanaque Reservoir, New Jersey's second-largest man-made lake (Round Valley Reservoir).
The Wanaque Reservoir begins to expand as it receives two additional tributaries: Ringwood Creek and Cupsaw Brook. The reservoir’s northern section is featured at lookouts found on nearby Governor, Board, Bear, and Windbeam mountains.
The northern half is also home to a nesting pair of bald eagles, referred to as “Wanaque A” by the NJ Department of Environmental Protection.
After flowing past Windbeam Mountain, the Wanaque Reservoir bottlenecks. West Brook Road crosses the reservoir at this midsection on a brand-new bridge completed in 2018. It replaces a narrow, 90-year-old bridge that fell into very poor shape, preserving an important route for Ringwood and West Milford residents. West Brook itself empties into the Wanaque Reservoir here, which now proceeds to expand to its greatest width.
Additional hills have lines of sight to the reservoir, including Assiniwikam Mountain, Wyanokie High Point, Carris Hill, and more. The area harbors its own pair of nesting eagles, designated “Wanaque B”.
The southern edge of the reservoir is bounded by several dams, such as the several “Green Swamp” dams. The largest of the entire reservoir, the 1500-foot Raymond Dam, is located to the southeast near the outflow of the Wanaque River. The dam appears very prominently from the nearby Wanaque Ridge.
The Wanaque River leaves the property of the Water Supply Commission and becomes accessible from Back Beach Park in Haskell, NJ. After intersecting with an underground natural gas pipeline, the river flows into a narrow valley between two ridges. Interstate 287 crosses over the river here, which is forced onto a large viaduct as a result of the valley’s depth. The viaduct is clearly identifiable from several hills in the region.
The river then enters an area with a history of munitions production, which has contaminated the neighborhood with mercury, lead, and other chemicals. It passes near the valley of the Acid Brook, the site of a former DuPont plant and even worse contamination. It passes through several culverts with one more major access point at Hershfield Park in Pompton Lakes. The Wanaque River ends near Carlough Field, joining with the Pequannock River to form the Pompton River, the most significant tributary of the Passaic River.
Bodies of Water in the Wyanokies
This article was built with information largely obtained from New York-New Jersey Trail Conference through its maps, books, and online resources. A trail guide by the American Ethical Union, obtained from the Highlands Natural Pool. Information from NJ DEP.