NOAA Web Site Link Tides and Currents Home Page Transparent placeholder image

Bench Mark Sheet for 8726769, MOBBLY BAYOU FL

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  5

                                                                                
Station ID: 8726769                         PUBLICATION DATE:  04/21/2003
Name:       MOBBLY BAYOU                                      
            FL
NOAA Chart: 11413                           Latitude:   28°  1.3' N (  28.02170)
USGS Quad:  OLDSMAR                         Longitude:  82° 39.3' W ( -82.65500)


To reach the tidal bench marks from the intersection of State Roads 584 and 580
(St Petersburg Drive), go SW along State Road 580 for 0.6 km (0.4 mi) to
Dartmouth Avenue (dirt road), turn left and go south on Dartmouth Avenue for 0.2
km (0.1 mi) to Lafayette Boulevard (dirt road), turn right onto Lafayette
Boulevard and go west for 0.2 km (0.1 mi) to National Orange Avenue (paved
road), turn left and go south on National Orange Avenue for 0.2 km (0.1 mi) to
Patty Drive, cross Patty Drive and continue south on a dim dirt road for 0.08 km
(0.05 mi) to a locked cable gate (Note:  The key may be obtained from the
Oldsmar Waste Water Treatment Plant, telephone #813-855- 4612), turn left and go
east through the gate for 0.2 km (0.1 mi) to a dim dirt road on the right, turn
right and go south for 0.5 km (0.3 mi) to a point where the road is on a narrow
dike.  The bench marks are along the dirt roads.  The tide gauge and staff were
on a platform at the south end of the dike.


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  6769 L 1990
                         DESIGNATION:          872 6769 L TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7582
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AL7928
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   28°  1.8' N (  28.03000)          LONGITUDE:  82° 39.7' W ( -82.66170)


The primary bench mark is a disk located at the intersection of Lafayette
Boulevard and National Orange Avenue, 16.86 m (55.3 ft) south of the centerline
of Lafayette Boulevard, 13.90 m (45.6 ft) SE of a four-trunked oak tree, 7.68 m
(25.2 ft) north of the centerline of a gravel road, and 0.88 m (2.9 ft) north of
a witness post.  The bench mark is crimped to the top of a stainless steel rod
driven to an unspecified depth.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  5

                                                                                
Station ID: 8726769                         PUBLICATION DATE:  04/21/2003
Name:       MOBBLY BAYOU                                      
            FL
NOAA Chart: 11413                           Latitude:   28°  1.3' N (  28.02170)
USGS Quad:  OLDSMAR                         Longitude:  82° 39.3' W ( -82.65500)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  6769 H 1983
                         DESIGNATION:          872 6769 H TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7580
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AL7372
SETTING CLASSIFICATION:  Concrete monument                     OPUS PID:        
LATITUDE:   28°  1.7' N (  28.02830)          LONGITUDE:  82° 39.6' W ( -82.66000)


The bench mark is a disk set in the top of a concrete monument under a high
tension power line tower, 361 m (1184 ft) north of bench mark 6769 M 1990 as
measured along the dim dirt road, 17.31 m (56.8 ft) NE of the intersection of
the dirt roads, 5.12 m (16.8 ft) NE of the SW leg of high tension power line
tower #HX13, 5.12 m (16.8 ft) SW of the NE leg of the tower, and level with the
ground.



                         BENCH MARK STAMPING:  6769 K 1990
                         DESIGNATION:          872 6769 K TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7583
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AL7927
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   28°  1.7' N (  28.02830)          LONGITUDE:  82° 39.7' W ( -82.66170)


The mark is a disk set along National Orange Avenue, 0.2 km (0.1 mi) south of
Lafayette Boulevard, 18.93 m (62.1 ft) north of a sanitary manhole cover, 7.74 m
(25.4 ft) west of the centerline of the northbound lane of National Orange
Avenue, 5.18 m (17.0 ft) east of the centerline of the southbound lane, and 0.91
m (3.0 ft) north of a witness post. The mark is crimped to the top of a
stainless steel rod driven to an unspecified depth.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  5

                                                                                
Station ID: 8726769                         PUBLICATION DATE:  04/21/2003
Name:       MOBBLY BAYOU                                      
            FL
NOAA Chart: 11413                           Latitude:   28°  1.3' N (  28.02170)
USGS Quad:  OLDSMAR                         Longitude:  82° 39.3' W ( -82.65500)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  6769 M 1990
                         DESIGNATION:          872 6769 M TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7584
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AL7926
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID:        
LATITUDE:   28°  1.5' N (  28.02500)          LONGITUDE:  82° 39.4' W ( -82.65670)


The bench mark is a disk set 131 m (430 ft) NW of bench mark 6769 N 1990 as
measured along the centerline of the dirt road, 9.72 m (31.9 ft) SE of a cabbage
palm, 6 m (19 ft) NE of the west edge of the dim dirt road, and 1.83 m (6.0 ft)
SW of a witness post.  The bench mark is crimped to the top of a stainless steel
rod driven to an unspecified depth.



                         BENCH MARK STAMPING:  6769 N 1990
                         DESIGNATION:          872 6769 N TIDAL

MONUMENTATION:           Tidal Station disk                    VM#:         7585
AGENCY:                  Florida Department of Natural Resources
                         (FLDNR)                               IDB PID#:  AL7925
SETTING CLASSIFICATION:  Stainless steel rod                   OPUS PID#: AL7925
LATITUDE:   28°  1.4' N (  28.02330)          LONGITUDE:  82° 39.4' W ( -82.65670)


The bench mark is a disk set SE of bench mark 6769 M 1990, 5 m (18 ft) NE of the
west edge of the dirt road, 4.36 (14.3 ft) SE of a cabbage palm, and 0.61 m (2.0
ft) SE of a witness post.  The bench mark is level with the ground, crimped to
the top of a stainless steel rod driven to an unspecified depth.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  5

                                                                                
Station ID: 8726769                         PUBLICATION DATE:  04/21/2003
Name:       MOBBLY BAYOU                                      
            FL
NOAA Chart: 11413                           Latitude:   28°  1.3' N (  28.02170)
USGS Quad:  OLDSMAR                         Longitude:  82° 39.3' W ( -82.65500)


                            T I D A L   D A T U M S 


Tidal datums at MOBBLY BAYOU based on:

     LENGTH OF SERIES:      1 Month
     TIME PERIOD:           August 1990 - August 1990
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  8726520 ST. PETERSBURG, TAMPA BAY


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:

     MEAN HIGHER HIGH WATER                     MHHW   =  0.538
     MEAN HIGH WATER                            MHW    =  0.431
     MEAN TIDE LEVEL                            MTL    =  0.242
     MEAN SEA LEVEL                             MSL    =  0.227
     North American Vertical Datum              NAVD88 =  0.224
     MEAN LOW WATER                             MLW    =  0.053
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     6769 L 1990                                 1.686    1.255
     6769 H 1983                                 2.009    1.578
     6769 K 1990                                 1.651    1.220
     6769 M 1990                                 1.278    0.847
     6769 N 1990                                 1.369    0.938


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  5

                                                                                
Station ID: 8726769                         PUBLICATION DATE:  04/21/2003
Name:       MOBBLY BAYOU                                      
            FL
NOAA Chart: 11413                           Latitude:   28°  1.3' N (  28.02170)
USGS Quad:  OLDSMAR                         Longitude:  82° 39.3' W ( -82.65500)


                             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.

Return to Top
Products available at 8726769 MOBBLY BAYOU, FL

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services