States

Lake Tappan

at Old Tappan, NJ · New Jersey · USGS gauge
5354555657
Water level · NGVD29
54.81FT
Gauge elevation · no % full published
7 days −0.21 ft30 days −0.09 ftvs last year +5.45 ft
Reading for Oct 25, 2026, 18:30 UTC · page refreshed Oct 25, 20:24 UTC
Source: U.S. Geological Survey (Water Data for the Nation)
Worth going today?This Afternoon
Looks good
Light wind, dry
Wind2 mph
Rain0%
Temp66°F
Level54.8 ft
This AfternoonSunny · 66°F
SW 2 mph · rain 0%
TonightClear · 41°F
SW 2 mph · rain 0%
NWS forecast for the gauge location. Good = wind ≤ 10 mph and rain ≤ 30%; storms are flagged. Not safety advice – check local conditions, closures and warnings.

Field notes

On Oct 25, 2026, Lake Tappan was at 54.81 (NGVD29) ft.

Over the past 7 days the lake has been falling (−0.21 ft), and it is −0.09 ft over 30 days.

Compared with a year ago (49.36 ft, same time of day), the lake is 5.45 ft higher.

Readings come from the USGS gauge “Lake Tappan at Old Tappan NJ”. USGS data are provisional and may be revised. Gauge elevations are not directly comparable between lakes because each uses its own datum.

Lake facts

Gauge / stationLake Tappan at Old Tappan NJ
Elevation datumft (NGVD29)
Gauge location41.0183, -74.0011

Nearby lakes

Woodcliff Lake3 mi W90.96 ft−0.18 ftOradell Reservoir5 mi S21.21 ft−0.80 ftWanaque Reservoir15 mi W290.76 ft−0.79 ftGreenwood Lake20 mi NW618.49 ft−0.08 ftBoonton Reservoir22 mi W305.37 ft−0.13 ft

Common questions

Is Lake Tappan rising or falling?

Over the last 7 days it changed −0.21 ft and over 30 days −0.09 ft.

How full is Lake Tappan?

USGS publishes the water surface elevation for this gauge but not a percent-full figure, so we don't show one rather than estimate it.

How often is this page updated?

The page is rebuilt automatically every day from USGS's published data. Values can be revised later by the source agency.

Where does the data come from?

The U.S. Geological Survey's Water Data API (api.waterdata.usgs.gov), which publishes readings from USGS and partner gauges. Forecasts come from the National Weather Service.

Latest instantaneous reading; 7-day, 30-day and year-ago changes compare readings at the same hour. USGS data are provisional and subject to revision. USGS data are provisional and subject to revision. This page is not affiliated with or endorsed by the USGS. See data sources.