The remote gauge may correlate differently to snow melt than rain. On 3/24/07 and 3/35/07 we had perfect medium flows as a results of snow melt. The Ramapo was reacting diurnally and fluctuated between a high of 884 cfs and 799 cfs during that time period. Conversely, I've paddled the Popolopen when the Ramapo peaked at 900 cfs after a rain event and had low water. A fall run that coincided with a peak of 1800 cfs on the Ramapo and the flow dropping to 1400 cfs during the time we were on the river yielded a strong medium-high level.
Although there is a fair degree of discrepancy between the Ramapo and the Popolopen, the rough correlation for rain events is as follows. When the Ramapo is rising:
700-1000 cfs = low
1000 cfs - 1600 cfs = medium
1600 cfs - 2000 cfs = high
2000 cfs and up = hair
Popolopen will usually hold water as long as the Ramapo is above 1000, but it will drop out more quickly than the Ramapo might suggest. If it's trending to be below 1000, it will probably be low or possibly too low, although if it's dropping slowly (less than 100 cfs in a 24 hour period), this may not hold true and you might have a fine water level.
So basically, levels above 700 cfs and holding or dropping slowly should correlate to a good runnable level. However, if it's been more than a day since it's rained you'll probably want to keep a close eye on how quickly the Ramapo is dropping or you might end up with low water.
Here's the original correlation established by Stephen Strange:
Lake Tiorati Br. has a drainage which is nearby and similar to Popolopen Br.'s. By comparing historical streamflow data from Lake Tiorati Br. and from the USGS gauge on the Ramapo R. at Mahwah, NJ, I was able to come up with a rough, but probably fairly accurate virtual gauge for Popolopen Br. It looks like Popolopen will most likely be running if snowmelt and/or rainfall spike the Ramapo R. at Mahwah, NJ to 700 cfs or over.
On the first-descent day, 12/22/02, the Ramapo was just coming down off of a 700-cfs peak. When I ran Popolopen Br. on 01/02/03 the Ramapo was peaking at 1900 cfs.
ducktales wrote, via the Northeast Paddlers' Massage Board, on 12-22-02, 11:02 AM (Eastern):
"First Descent of New Class 4-5 Creek"
Mark J. had been eyeballing it for years before four of us decided yesterday to go for a first descent of Popolopen Brook, a steep creek in New York's Bear Mountain area. Between the snowmelt and Friday's rains, the creek was running at a nice "medium" level; there's no gauge or standard for measuring levels at this point. It's an absolute gem, decidedly more difficult than the West Branch of the Deerfield; for me, it recalled Vermont's Big Branch and West Virginia's Decker's Creek, each of which I've been on only once. But Popolopen is unique, clear water running continuously at about a 300 feet per mile gradient, with a couple of spectacular drops. It's amazing that this hasn't been discovered until now, considering how close it is to New York City; the run ends at the Bear Mountain Bridge, tumultuously tumbling out of the Orange County hills until abruptly stopping at the Hudson River. We could use a cleaning party of boaters with handsaws before the next descent, since there is some wood that really should be removed.
Stephen Strange added:
"I was lucky enough to be in the area a week and a half later with water to spare. I would definitely compare this run to Action Alley on Big Cr. (NC) at over 2 ft, except that this keeps going."
|Ramapo River near Mahwah NJ|
|usgs-01387500||700 - 2000 cfs||V||00h27m||142 cfs (too low)|
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