U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 5
Station ID: 8770520 PUBLICATION DATE: 10/14/2020
Name: RAINBOW BRIDGE, NECHES RIVER
TX
NOAA Chart: 11342 Latitude: 29° 58.8' N ( 29.98000)
USGS Quad: PORT ARTHUR NORTH Longitude: 93° 52.9' W ( -93.88170)
To reach the tide station from the intersection of Atlantic Road and 32nd Street
in the city of Groves, enter the "Total" plant at the NE side of the
intersection and go to their loading docks on the Neches river. The tide gauge
and staff are located on the west side of dock 2. The benchmarks are located
along the road and parking lot for dock 2.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: LUB 0520 B 1992
DESIGNATION: 877 0520 B
MONUMENTATION: Bench Mark disk VM#: 16779
AGENCY: Lamar University Beaumont (LUB) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 58.8' N ( 29.98014) LONGITUDE: 93° 52.9' W ( -93.88161)
The primary bench mark is a brass disk located 315.0 m (1033.4 ft) East from the
tide staff near a utility pole, 4.00 m (13.1 ft) North of the center of the
road, marked with an orange witness post, crimped onto a stainless steel rod
driven 16.8 m (55 ft) to refusal, encased in a 6" PVC pipe with concrete
kickblock set flush with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 8770520 PUBLICATION DATE: 10/14/2020
Name: RAINBOW BRIDGE, NECHES RIVER
TX
NOAA Chart: 11342 Latitude: 29° 58.8' N ( 29.98000)
USGS Quad: PORT ARTHUR NORTH Longitude: 93° 52.9' W ( -93.88170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: LUB 0520 A 1992
DESIGNATION: 877 0520 A
MONUMENTATION: Bench Mark disk VM#: 16778
AGENCY: Lamar University Beaumont (LUB) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID:
LATITUDE: 29° 58.8' N ( 29.98006) LONGITUDE: 93° 52.8' W ( -93.88056)
The bench mark is a brass disk located 8.50 m (27.8 ft) North of the centerline
of the road, 2.50 m (8.2) ft) North of the southern edge of the concrete
containment curb, crimped onto a stainless steel rod driven 16.8 m (55 ft) to
refusal, encased in a 6" PVC pipe with concrete kickblock set flush with the
ground.
BENCH MARK STAMPING: LUB 0520 D 1992
DESIGNATION: 877 0520 D
MONUMENTATION: Bench Mark disk VM#: 16781
AGENCY: Lamar University Beaumont (LUB) IDB PID#: DL4467
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: DL4467
LATITUDE: 29° 58.8' N ( 29.97928) LONGITUDE: 93° 53.0' W ( -93.88286)
The bench mark is a brass disk located 90.00 m (295.3 ft) SW of bench mark LUB
0520 C, 3.80 m (12.5 ft) W of the centerline of the road, 0.30 m (1.0 ft) from a
utility pole beside the road, crimped onto a stainless steel rod driven 16.8 m
(55 ft) to refusal, encased in a 6" PVC pipe with concrete kickblock set flush
with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 8770520 PUBLICATION DATE: 10/14/2020
Name: RAINBOW BRIDGE, NECHES RIVER
TX
NOAA Chart: 11342 Latitude: 29° 58.8' N ( 29.98000)
USGS Quad: PORT ARTHUR NORTH Longitude: 93° 52.9' W ( -93.88170)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: LUB 0520 E 1992
DESIGNATION: 877 0520 E
MONUMENTATION: Bench Mark disk VM#: 16782
AGENCY: Lamar University Beaumont (LUB) IDB PID:
SETTING CLASSIFICATION: Stainless steel rod OPUS PID#: BBFY15
LATITUDE: 29° 58.7' N ( 29.97853) LONGITUDE: 93° 53.0' W ( -93.88314)
The bench mark is a brass disk located about 80.00 m (262.5 ft) SW of bench mark
LUB 0520 D, 3.50 m (11.5 ft) West of the centerline of the road, 0.30 m (1 ft)
from a utility pole at a bend in the road, marked with an orange witness post,
crimped onto a stainless steel rod driven 16.8 m (55 ft) to refusal and is
encased in a 6" PVC pipe with concrete kickblock set flush with the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 8770520 PUBLICATION DATE: 10/14/2020
Name: RAINBOW BRIDGE, NECHES RIVER
TX
NOAA Chart: 11342 Latitude: 29° 58.8' N ( 29.98000)
USGS Quad: PORT ARTHUR NORTH Longitude: 93° 52.9' W ( -93.88170)
T I D A L D A T U M S
Tidal datums at RAINBOW BRIDGE, NECHES RIVER based on:
LENGTH OF SERIES: 4 YEARS
TIME PERIOD: 10/12-9/13, 9/15-8/17, 10/17-9/18
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8770570 SABINE PASS NORTH
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
HIGHEST OBSERVED WATER LEVEL (08/30/2017) = 1.204
MEAN HIGHER HIGH WATER MHHW = 0.299
MEAN HIGH WATER MHW = 0.284
MEAN SEA LEVEL MSL = 0.169
MEAN TIDE LEVEL MTL = 0.161
North American Vertical Datum NAVD88 = 0.130
MEAN LOW WATER MLW = 0.037
MEAN LOWER LOW WATER MLLW = 0.000
LOWEST OBSERVED WATER LEVEL (01/19/1996) = -0.771
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
LUB 0520 B 1992 1.356 1.072
LUB 0520 A 1992 1.167 0.883
LUB 0520 D 1992 1.007 0.723
LUB 0520 E 1992 0.788 0.504
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 8770520 PUBLICATION DATE: 10/14/2020
Name: RAINBOW BRIDGE, NECHES RIVER
TX
NOAA Chart: 11342 Latitude: 29° 58.8' N ( 29.98000)
USGS Quad: PORT ARTHUR NORTH Longitude: 93° 52.9' W ( -93.88170)
D E F I N I T I O N S
Mean Sea Level (MSL) is a tidal datum determined over a 19-year National Tidal
Datum Epoch. It pertains to local mean sea level and should not be confused
with the fixed datums of North American Vertical Datum of 1988 (NAVD88).
NAVD88 is a fixed datum derived from a simultaneous, least squares, minimum
constraint adjustment of Canadian/Mexican/United States leveling observations.
Local mean sea level observed at Father Point/Rimouski, Canada was held fixed as
the single initial constraint. NAVD88 replaces NGVD29 as the national
standard geodetic reference for heights. Bench mark elevations relative to
NAVD88 are available from NGS through the World Wide Web at
National Geodetic Survey.
NGVD29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded. NGVD29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads. NGVD29 was originally derived from a general
adjustment of the first-order leveling networks of the U.S. and Canada after
holding mean sea level observed at 26 long term tide stations as fixed.
Numerous local and wide-spread adjustments have been made since establishment in
1929. Bench mark elevations relative to NGVD29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at
National Geodetic Survey.
NAVD88 and NGVD29 are fixed geodetic datums whose elevation relationships to
local MSL and other tidal datums may not be consistent from one location to
another.
The Vertical Mark Number (VM#) and PID# shown on the bench mark sheet are unique
identifiers for bench marks in the tidal and geodetic databases, respectively.
Each bench mark in either database has a single, unique VM# and/or PID# assigned.
Where both VM# and PID# are indicated, both tidal and geodetic elevations are
available for the bench mark listed. The NGS's Integrated Data Base (IDB PID)
provides geodetic datum based on traditionally leveled and bluebooked ties to
the National Spatial Reference System(NSRS) https://www.ngs.noaa.gov/datasheets/.
The NGS Online Positioning User Service (OPUS PID) provides geodetic datum based
on GPS position & tie it to the NSRS https://www.ngs.noaa.gov/OPUS/.
The NAVD88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD88 elevations.
The NAVD88 elevation relationship shown in the table is derived from an average
of several bench mark elevations relative to tide station datum. As a result of
this averaging, NAVD88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD88 elevations listed for
each bench mark in the NGS database.