U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 1 of 5
Station ID: 9415117 PUBLICATION DATE: 10/02/1981
Name: BISHOP CUT, DISAPPOINTMENT SLOUGH
CALIFORNIA
NOAA Chart: 18661 Latitude: 38ø 2.6' N
USGS Quad: TERMINOUS Longitude: 121ø 25.1' W
To reach the tidal bench marks proceed to the west side of Bishop Tract, 0.6
mile south along Rio Blancos Road from junction with Eight Mile Road and
drawbridge over Bishop Cut. The tide gage and staff were located on the
floating dock at Paradise Point Marina.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 5117 A 1979
MONUMENTATION: Survey Disk VM#: 8570
AGENCY: PID:
SETTING CLASSIFICATION: Galvanized Steel Deep Rod
The bench mark is set on a galvanized steel rod driven 32 feet to refusal,
encased in PVC pipe (extends one foot above grade), 60 feet west of public
telephone booth, 32 feet south-southwest of southwest corner of office at
Paradise Point Marina, 6 feet northeast of bank of slough, and 0.1 foot above
grade.
BENCH MARK STAMPING: NO 3 1933
MONUMENTATION: Survey Disk VM#: 8569
AGENCY: PID#: JS1157
SETTING CLASSIFICATION: Concrete Foundation
The bench mark is set vertically in the east end of north wall of concrete
foundation for a former pumphouse, 80 feet east of centerline of Rio Blanco
Road, 39.8 feet northwest of northwest corner of pumphouse, 24 feet north of
center of more northerly of two steel discharge pipes (extending out from
pumphouse), and 1.7 feet above ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 5
Station ID: 9415117 PUBLICATION DATE: 10/02/1981
Name: BISHOP CUT, DISAPPOINTMENT SLOUGH
CALIFORNIA
NOAA Chart: 18661 Latitude: 38ø 2.6' N
USGS Quad: TERMINOUS Longitude: 121ø 25.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 5117 B 1979
MONUMENTATION: Survey Disk VM#: 8571
AGENCY: PID:
SETTING CLASSIFICATION: Steel Deep Rod
The bench mark is crimped onto steel rod driven 30 feet to refusal, encased in
PVC pipe (extends one foot above grade), 0.2 mile north of Paradise Point
Marina Restaurant along Rio Blancos Road, 19 feet east of centerline of Rio
Blancos Road, 2.3 feet north of telephone pole No. 15 (near intersection of
dirt road and Rio Blancos Road), and 0.2 foot below grade.
BENCH MARK STAMPING: 5117 D 1979
MONUMENTATION: Survey Disk VM#: 8572
AGENCY: PID:
SETTING CLASSIFICATION: Steel Deep Rod
The bench mark is crimped onto steel rod driven 32 feet to refusal, encased in
PVC pipe, 0.35 mile north along Rio Blancos Road from Bench Mark No. 3 1933,
75.4 feet northwest of northwest corner of abandoned farmhouse, 39 feet east of
centerline of Rio Blancos Road, 2.3 feet south-southwest of telephone No. 9580,
one foot southeast of witness post, and 0.5 foot below grade.
BENCH MARK STAMPING: MDC 1974
MONUMENTATION: Survey Disk VM#: 8573
AGENCY: PID:
SETTING CLASSIFICATION: Steel Rod
The bench mark is set on a steel rod 120 feet southwest of northwest corner of
Paulin Bridge over Disappointment Slough, 30 feet northwest of northwest corner
of cement boat launching travel lift, 6.5 feet north of northeast corner of
windmill pumphouse at marina, and 4 feet east of telephone pole.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 5
Station ID: 9415117 PUBLICATION DATE: 10/02/1981
Name: BISHOP CUT, DISAPPOINTMENT SLOUGH
CALIFORNIA
NOAA Chart: 18661 Latitude: 38ø 2.6' N
USGS Quad: TERMINOUS Longitude: 121ø 25.1' W
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: Q 464 1951
MONUMENTATION: Survey Disk VM#: 8574
AGENCY: PID#: JS1156
SETTING CLASSIFICATION: Concrete Pier
The bench mark is set in top of concrete pier at northwest corner of drawspan,
on east side of King Island at drawbridge over the Cut, 39.2 feet east of
northwest corner of bridge, 13 feet north of centerline of Eight Mile Road, and
3 feet below road.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 5
Station ID: 9415117 PUBLICATION DATE: 10/02/1981
Name: BISHOP CUT, DISAPPOINTMENT SLOUGH
CALIFORNIA
NOAA Chart: 18661 Latitude: 38ø 2.6' N
USGS Quad: TERMINOUS Longitude: 121ø 25.1' W
T I D A L D A T U M S
Tidal datums at BISHOP CUT, DISAPPOINTMENT SLOUGH based on:
LENGTH OF SERIES: 5 MONTHS
TIME PERIOD: JULY - NOVEMBER 1979
TIDAL EPOCH: 1960-1978
CONTROL TIDE STATION:
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in FEET:
MEAN HIGHER HIGH WATER (MHHW) = 3.86
MEAN HIGH WATER (MHW) = 3.43
MEAN TIDE LEVEL (MTL) = 1.96
* NATIONAL GEODETIC VERTICAL DATUM-1929 (NGVD) = 0.77
MEAN LOW WATER (MLW) = 0.49
MEAN LOWER LOW WATER (MLLW) = 0.00
* NGVD reference based on adjustments of 1968, and NOS levels of 1979.
Bench Mark Elevation Information In FEET above:
Stamping or Designation MLLW MHW
5117 A 1979 5.33 1.90
NO 3 1933 -4.29 -7.72
5117 B 1979 7.25 3.82
5117 D 1979 2.91 -0.52
MDC 1974 8.75 5.32
Q 464 1951 8.76 5.33
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 5
Station ID: 9415117 PUBLICATION DATE: 10/02/1981
Name: BISHOP CUT, DISAPPOINTMENT SLOUGH
CALIFORNIA
NOAA Chart: 18661 Latitude: 38ø 2.6' N
USGS Quad: TERMINOUS Longitude: 121ø 25.1' W
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 (NAVD 88).
NGVD 29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded. NGVD 29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads. NGVD 29 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 NGVD 29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at
National Geodetic Survey.
NAVD 88 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. NAVD 88 replaces NGVD 29 as the national
standard geodetic reference for heights. Bench mark elevations relative to
NAVD 88 are available from NGS through the World Wide Web at
National Geodetic Survey.
NGVD 29 and NAVD 88 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 NAVD 88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD 88 elevations.
The NAVD 88 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, NAVD 88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD 88 elevations listed for
each bench mark in the NGS database.