U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Datums Page Page 1 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
From the US Post Office at 5124 Ocean Blvd, proceed north 0.6 km (0.4 mi) on
Ocean Blvd to the intersection with Givens Street on the right and a public
access walkway on the left, turn left and proceed west down the public access
walkway 70m (230 ft) west to the seawall and the station on the left. The bench
marks are located throughout the city west of Roberts Bay. The tide station is
located on the seawall.
T I D A L B E N C H M A R K S
PRIMARY BENCH MARK STAMPING: 6034 A 2019
DESIGNATION: 872 6034 A
MONUMENTATION: Tidal Station disk VM#: 23361
AGENCY: National Ocean Service (NOS) IDB PID:
SETTING CLASSIFICATION: Concrete seawall OPUS PID#: BBGR73
LATITUDE: 27° 17.0' N ( 27.28386) LONGITUDE: 82° 33.9' W ( -82.56500)
The primary bench mark is a disk set in a concrete seawall at the western end of
Givens St, 23.99 m (78.7 ft) WNW of the corner of a concrete wall at the end of
an asphalt access road, 9.30 m (30.5 ft) ENE of the corner of a sidewalk-seawall
at a fence line for a property to the south, 5.82 m (19.1 ft) NE of a concrete
seawall along a property to the south and 1.17 m (3.8 ft) WSW of a higher
seawall for new condo buildings.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 2 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: R 79 1-12-79
DESIGNATION: R 79
MONUMENTATION: Survey disk VM#: 23362
AGENCY: FL-081 Manatee County, FL IDB PID#: DL1800
SETTING CLASSIFICATION: OPUS PID:
LATITUDE: 27° 17.4' N ( 27.28956) LONGITUDE: 82° 33.5' W ( -82.55894)
The bench mark is a disk set in a 13 cm (5 inches) square concrete post, 32.19 m
(105.6 ft) north of the front and center edge of a park bench, 6.25 m (20.5 ft)
south-SSE of a pedestrian crossing signal, 5.12 m (16.8 ft) SW of another
pedestrian crossing signal, 3.05 m (10.0 ft) south of a post for a sign for Boyd
Park and 14 cm (6 inches) above the ground.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 3 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: GC
DESIGNATION: GC
MONUMENTATION: Survey disk VM#: 23363
AGENCY: FLSRD IDB PID#: DL1863
SETTING CLASSIFICATION: Bridge curb OPUS PID:
LATITUDE: 27° 17.1' N ( 27.28489) LONGITUDE: 82° 33.3' W ( -82.55517)
The bench mark is a disk set in the east concrete curb on the SE end of a bridge
along Midnight Pass Road, 29.29 m (96.1 ft) SE of a nail near the northern end
of a bridge on the eastern side marked Sarasota County bench mark 79-B, 4.45 m
(14.6 ft) NE of the centerline of the road, 2.38 m (7.8 ft) west of the SE end
of a concrete railing along a walkway, 0.49 m (1.6 ft) SW of the western side of
a concrete railing and 28 cm (11 inches) higher than the road.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 4 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: Z 700 2007
DESIGNATION: Z 700
MONUMENTATION: Survey disk VM#: 23364
AGENCY: FLDEP IDB PID#: DL1801
SETTING CLASSIFICATION: OPUS PID:
LATITUDE: 27° 16.5' N ( 27.27422) LONGITUDE: 82° 32.8' W ( -82.54711)
The bench mark is a disk set in a vine covered garden with a sign for St Michael
the Arch Angel Catholic Church, 25.88 m (84.9 ft) NNE of the center of double
doors that enter to the church, 11.43 m (37.5 ft) NW of a sign for St Michael
the Arch Angel Church, 8.93 m (29.3 ft) WSW of the centerline of Midnight Pass
Road, 4.11 m (13.5 ft) ENE of the face of a curb along the SW side of a road
island, 1.64 m (5.4 ft) SSE of the face of power pole 514 634 485 07, 0.73 m
(2.4 ft) SE of a carsonite witness post that stands 12 cm (5 inches) above a
shell fill ground and 10 cm (4 inches) below the ground.
BENCH MARK STAMPING: 25696 C
DESIGNATION: 25696 C 2014
MONUMENTATION: Survey disk VM#: 23366
AGENCY: Southwest Florida Water Management
District IDB PID#: DP6065
SETTING CLASSIFICATION: OPUS PID#: DP6065
LATITUDE: 27° 16.0' N ( 27.26704) LONGITUDE: 82° 33.0' W ( -82.55061)
The bench mark is a disk set on the north side of a parking lot that is to the
south of Beach Road, 14.39 m (47.2 ft) NE of the westernmost of two "do not
enter" signs, 10.91 m (35.8 ft) south of a power pole, 5.03 m (16.5 ft) WSW of a
palm tree, 2.55 m (8.4 ft) WNW of a curb to the east, 1.90 m (6.2 ft) ESE of a
curb to the west and 0.39 m (1.3 ft) south of the face of a well. The datum
point is the top of a disk set 5 cm (2 inches) below ground crimped to the top
of an aluminum rod driven 3.9 m (12.8 ft) and encased in concrete.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 5 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: 25696 D
DESIGNATION: 25696 D 2014
MONUMENTATION: Survey disk VM#: 23367
AGENCY: Southwest Florida Water Management
District IDB PID#: DP6066
SETTING CLASSIFICATION: OPUS PID:
LATITUDE: 27° 16.0' N ( 27.26711) LONGITUDE: 82° 33.0' W ( -82.55064)
The bench mark is a disk set in a parking island on the north side of a parking
lot that is to the south of Beach Road, 14.08 m (46.2 ft) NNE of the westernmost
of two "do not enter signs" in the parking lot, 9.69 m (31.8 ft) south of power
pole 926 standing along the road, 4.24 m (13.9 ft) WSW of a palm tree at the
edge of the parking lot, 2.6 m (8.5 ft) WNW of the top-back of curb to the east,
1.89 m (6.2 ft) ESE of the top-back of curb to the west, 0.89 m (2.9 ft) SSW of
a 3.05 m (10.0 ft) high metal post with a sensor on top and 0.49 m (1.6 ft) NNE
of a large well with an electronics box on top. The datum point being the top
of a disk set 5 cm (2 inches) below ground crimped to the top of an aluminum rod
driven 11.4 m (37.4 ft) and encased in concrete.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 6 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
T I D A L B E N C H M A R K S
BENCH MARK STAMPING: SAR 101
DESIGNATION: SAR 101
MONUMENTATION: Tidal Station disk VM#: 23368
AGENCY: IDB PID:
SETTING CLASSIFICATION: OPUS PID:
LATITUDE: 27° 16.0' N ( 27.26750) LONGITUDE: 82° 33.3' W ( -82.55553)
The bench mark is set near a sand dune at the southeastern end of Sarasota
Beach, 34.02 m (111.6 ft) SW of a power pole along the road, 31.52 m (103.4 ft)
ENE of the western support for the westernmost support of a picnic shelter,
15.09 m (49.5 ft) SE of a rope that runs along a trail to the beach, 13.32 m
(43.7 ft) SW of the center-front edge of a park bench and 0.26 m (0.9 ft) ENE of
a carsonite witness post.
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 7 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
T I D A L D A T U M S
Tidal datums at SIESTA KEY, BIG SARASOTA PASS based on:
LENGTH OF SERIES: 7 MONTHS
TIME PERIOD: January 2020 - July 2020
TIDAL EPOCH: 1983-2001
CONTROL TIDE STATION: 8726724 CLEARWATER BEACH, GULF OF MEXICO
Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:
MEAN HIGHER HIGH WATER MHHW = 0.618
MEAN HIGH WATER MHW = 0.534
North American Vertical Datum NAVD88 = 0.483
MEAN SEA LEVEL MSL = 0.321
MEAN TIDE LEVEL MTL = 0.321
MEAN LOW WATER MLW = 0.108
MEAN LOWER LOW WATER MLLW = 0.000
North American Vertical Datum (NAVD88)
Bench Mark Elevation Information In METERS above:
Stamping or Designation MLLW MHW
6034 A 2019 1.883 1.349
R 79 1-12-79 1.596 1.062
GC 5.723 5.189
Z 700 2007 1.947 1.413
25696 C 1.709 1.175
25696 D 1.718 1.184
SAR 101 1.868 1.334
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Ocean Service
Page 8 of 8
Station ID: 8726034 PUBLICATION DATE: 02/22/2021
Name: SIESTA KEY, BIG SARASOTA PASS
FL
NOAA Chart: 11424 Latitude: 27° 17.0' N ( 27.28389)
USGS Quad: SARASOTA Longitude: 82° 33.9' W ( -82.56500)
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.