U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2007-3064

August 2007

New Jersey Tide Telemetry System

Printed on recycled paper

Each summer the population of the 

barrier-island communities of New Jersey 

increases by tens of thousands. When a 

coastal storm threatens these communities, the limited number of bridges and 

causeways that connect the islands with 

the mainland become overcrowded, making evacuations from the barrier islands 

to the mainland difficult. Timely evacuation depends on well-defined emergency 

evacuation plans used in conjunction with 

accurate flood forecasting and up to the 

minute (real-time) tide-level information.

The “Great Nor’easter” storm that 

struck the coastal areas of New Jersey on 

December 11, 1992, caused about $270 

million in insured damages to public 

and private property (Dorr and others, 

1995). Most of the damage was due to 

tidal flooding and storm surge, which 

were especially severe along the back 

bay areas. Comprehensive and reliable 

tide-level and meteorological data for the 

back bays was needed to make accurate 

flood forecasts.

Collection of tidal data for the ocean 

and large bays was adequately covered 

by the National Oceanic and Atmospheric 

Administration’s National Ocean Service 

(NOAA’s NOS), but in New Jersey little 

to no data are available for the back-bay 

areas. The back bays behave quite differently than the ocean as a result of the 

complex interaction between the winds 

and the geometry of the inlets and bays. 

A slow moving Nor’easter can keep tide 

levels in back bays several feet higher 

than the ocean tide by not allowing tides 

to recede, resulting in flooding of bridges 

and causeways that link the barrier 

islands to the mainland.

The U.S. Geological Survey 

(USGS), in cooperation with the New 

Jersey Department of Transportation 

(NJDOT), designed and installed the 

New Jersey Tide Telemetry System 

(NJTTS) with assistance from NOAA’s 

NOS in 1997. This system is part of a 

statewide network of tide gages, weather 

stations, and stream gages that collect 

data in real time. The NJTTS supplies Figure 1. Locations of gages in the New Jersey Tide Telemetry System.

VA LLEY 

AND 

RIDGE

NEW ENGLAND

P I E D M O N T

C O A S T A L 

P L A I N

0

0

Physiographic province

boundary

EXPLANATION

75 74 

41 

40 

39 

SUSSEX

WARREN

MORRIS

HUNTERDON

PASSAIC

BERGEN

ESSEX

UNION

SOMERSET

MIDDLESEX

MERCER

MONMOUTH

HUDSON

BURLINGTON

CAMDEN

GLOUCESTER

OCEAN

SALEM

ATLANTIC

CUMBERLAND

CAPE

MAY

10

10

20 MILES

20 KILOMETERS DELAWARE

PENNSYLVANIA

NEW YORK

NEW JERSEY

New York

City

Trenton

Philadelphia

ATLANTIC

OCEAN

DELAWARE

BAY

RARITAN

BAY

Newark

Bay

Delaware

River

Passaic River

Basin

Rahway River

Basin

Pascack Brook

Basin

Burlington County

Somerset County

Tide gage station

Tide/weather station

Tide crest-stage gage site

Fall Line
comprehensive, reliable real-time tidelevel and meteorological data for floodprone areas along the New Jersey shore 

and back bays. These data are transmitted to computer base stations located at 

offices of the National Weather Service, 

New Jersey State Police (NJSP), NJDOT, 

county emergency management agencies, 

other critical decision-making centers, 

and the World Wide Web (WWW). This 

fact sheet describes the NJTTS and identifies its benefits.

DESCRIPTION OF STUDY AREA

The study area covers the coastal 

regions of New Jersey, including the barrier islands, the back bays, the near-shore 

environment from Hackensack to Cape 

May, the Delaware Bay, and the Delaware River (fig. 1). Most of the area lies 

within the Coastal Plain Physiographic 

Province, which is characterized by 

elevations typically less than 100 feet 

above North American Vertical Datum of 

1988 and by marshes bordering numerous streams and estuaries (Wolfe, 1977) 

(fig. 1). A small portion of the study 

area, in northeast New Jersey, lies within 

the Piedmont Physiographic Province 

(Wolfe, 1977).

NEW JERSEY TIDE TELEMETRY 

SYSTEM

The NJTTS presently consists of 

20 tide gages, 5 tide/weather stations, and 

31 tidal crest-stage gages in 13 New Jersey counties, along the New Jersey shore 

and nearby areas (fig. 1, fig. 2, fig. 3, 

and fig. 4). The tide level at each of the 

tide gages is automatically measured 

at 6-minute intervals, stored by a datacollection platform (DCP), and transmitted by NOAA’s GOES (Geostationary 

Operational Environmental Satellite) 

satellite to the network of computer base 

stations and the World Wide Web. The 

data also are transmitted by telephone to 

specific critical decision-making centers. 

The weather stations measure, store, and 

transmit tide levels and meteorological 

data—rainfall, windspeed and direction, 

air and water temperature, relative 

humidity, and barometric pressure—

using the same modes of telemetry. The 

tidal crest-stage gages, simple, nonmechanical devices that can only be 

read manually, record the peak tide level 

between inspections. These gages provide 

redundancy during primary sensor failure 

and verification of recorded peaks.

Precise land-surface elevations 

have been established for each location 

in the NJTTS. The elevations are part 

of a network of benchmarks, which are 

permanent markers on which a known 

elevation is established. The benchmarks 

are referenced to the North American 

Vertical Datum of 1988.

The base stations consist of computers and peripheral equipment, which 

receive, store, and translate the data transmitted by the gages. They are located in 

State, county, or municipal offices where 

they are available to emergency management personnel who use the real-time 

data to make immediate decisions about 

evacuation routes. The base stations 

associated with the NJTTS are located 

in the Offices of Emergency Management of Atlantic, Cape May, Cumberland, 

Monmouth, and Ocean Counties, as well 

as the NJDOT office in Trenton, N.J., and 

the regional offices.

Figure 2. USGS tide gage/weather station at Absecon Channel in Atlantic City, NJ, which 

transmits tide-level and meteorologic data.
LINKS WITH OTHER SYSTEMS

At present (2007), five local floodwarning systems, in addition to the 

NJTTS, are in operation in New Jersey—

the Burlington County Flood Warning 

System (BCFWS), the Pascack Brook 

Flood Warning System (PBFWS), the 

Passaic Flood Warning System (PFWS), 

the Rahway River Flood Warning System 

(RRFWS), and the Somerset County 

Flood Information System (SCFIS)

(fig. 1).

The BCFWS, which has been in 

use since 1964, uses 10 stream stage and 

3 precipitation gages to monitor stream 

levels and rainfall in Burlington County; 

the PBFWS, in use since 1998, uses 4 

stream stage and 3 precipitation gages 

to monitor the Pascack Brook Basin; 

the PFWS, in use since 1903, uses 21 

stream stage and 35 precipitation gages 

to monitor the Passaic River Basin; 

the RRFWS, in use since 1964, uses 7 

stream stage and 3 precipitation gages 

in monitor the Rahway River Basin; and 

the SCFIS, in use since 1990, uses 28 

stream stage and 21 precipitation gages to 

monitor Somerset County. Each system 

consists of automated stream gages and 

precipitation gages that are transmitted to 

computer base stations and the WWW by 

telephone, radio, and (or) satellite link.

BENEFITS OF THE NJTTS

Tide-level and meteorological data 

collected and transmitted by the NJTTS 

can be used in real time or stored and 

later retrieved by Federal, State, county, 

and municipal agencies, as well as the 

public, for a variety of purposes that benefit the residents of New Jersey.

•	 Tide-level data from the back bays can 

be used to determine conditions that 

would necessitate evacuations during 

coastal storms and hurricanes, allowing emergency management personnel to prepare emergency routes and 

responses well in advance of a storm.

•	 Real-time tide-level data from the back 

bays could be used to determine road 

and causeway closures and emergency 

evacuation routes for immediate use 

during coastal storms or hurricanes.

•	 Real-time knowledge of back bay tide 

levels can allow commercial business 

and industry to take actions to reduce 

inventory and structural losses during 

storms.

•	 Tide-level and rainfall data can be used 

as historical data by future planners to 

determine peak water elevations, mean 

high water (MHW), and 100-year 

flood elevations.

•	 Peak water levels and MHW data 

can be used for the design of bridges. 

Roads and culverts can be located in 

areas that are not prone to flooding 

and where they are not likely to cause 

flooding in adjacent areas.

•	 MHW and 100-year flood elevations 

can be used to determine appropriate 

permitting requirements of the NJDEP, 

and other State and Federal agencies.

•	 MHW data and 100-year flood elevations can be used to determine whether 

surface-water levels have changed as 

a result of a change in sea level, land 

subsidence, or changes in channel 

geometry.

•	 Precise land-surface elevations 

obtained from the network of benchmarks will be incorporated into the 

NJDOT Geodetic Control Survey 

database.

•	 Tide level and meteorological data can 

be used for long-term studies such as 

global warming.

ACCESS TO THE DATA

The tide-level and meteorological 

data from this network, as well as data 

from gages which are part of the New 

Jersey statewide system, can be accessed 

on the WWW at the USGS New Jersey 

Water Science Center homepage at http://

nj.usgs.gov/ under the heading Real-Time 

Data. A graph of the tide-level and meteorological data for the last 7 days (fig. 5) is 

available by clicking on a specific station. 

These data are also available on NOAA’s 

NWS Advanced Hydrologic Prediction 

Service (AHPS) website at www.weather.

gov/ahps/ and at NOAA’s nowCOAST 

website at http://nowcoast.noaa.gov/. 

Real-time flood-warning data that are 

not transmitted by satellite, but rather 

by radio telemetry on an event reporting 

basis can be viewed at the Automated 

Flood Warning Systems website at http://

www.afws.net/.

A new mode of accessing data 

from USGS real-time stations is through 

USGS StreamMail. This service provides 

immediate water information from the 

USGS Real-Time Network to devices 

such as cell phones and personal digital 

assistants. Send an email to streammail@

usgs.gov with a USGS station number in 

the subject line and after a few minutes 

you will receive an e-mail with the most 

recent real-time stage and streamflow 

data.

Figure 3. USGS tide gage at Barnegat Bay 

in Mantoloking, NJ, which transmits tidelevel data.

Figure 4. USGS tide gage at Barnegat Bay 

in Waretown, NJ, which transmits tide-level 

data.
Figure 5. Example of an actual tide-level graph that can be viewed and printed from the 

“Real-Time Data” web page.

REFERENCES CITED

Dorr, R.A., Thurm, Harvey, Shaffer, 

Wilson, Kocin, Paul, Kramper, James, 

Kane, Richard, Graff, S.K., Budd, 

Bruce, Gabrielsen, Peter, Hrebanach, 

Stephen, 1995, The Great Nor’Easter 

of December 1992: National Weather 

Service Eastern Region, Disaster Survey Report, 112 p.

Wolfe, P.E., 1977, The geology and 

landscapes of New Jersey: New York, 

Crane, Russak and Company, Inc., 

351 p.

For more information, contact:

New Jersey Water Science Center

U.S. Geological Survey

810 Bear Tavern Rd., Suite 206

West Trenton, NJ 08628

On the web: http://nj.usgs.gov/

Email: DC_NJ@usgs.gov

Partners in project:

National Oceanic and Atmospheric Administration (NOAA)

http://www.noaa.gov/

New Jersey Department of Transportation (NJDOT)

http://www.state.nj.us/transportation/

New Jersey Office of Emergency Management (NJOEM)

http://www.state.nj.us/njoem/

by Heidi L. Hoppe