LEVELING DETERMINING DIFFERENCES IN ELEVATION BETWEEN POINTS ELEVATION IS VERTICAL DISTANCE ABOVE OR

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LEVELING DETERMINING DIFFERENCES IN ELEVATION
BETWEEN POINTS ELEVATION IS VERTICAL DISTANCE
ABOVE OR BELOW A REFERENCE DATUM ASSUMED
DATUM MEAN SEA LEVEL (MSL) BENCHMARKS
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LEVELING EQUIPMENT AUTOMATIC LEVEL TRIPOD GRAD
E ROD HUBS
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LEVELING DEFINITIONSBENCHMARK (BM) A PERMANENT
POINT OF KNOWN ELEVATION THERE ARE SEVERAL BMS
AROUND CAMPUSTEMPORARY BENCHMARK (TBM) A SEMI
PERMANENT POINT OF KNOWN OR ASSUMED ELEVATION
(TOP OF HYDRANT, MH COVER ETC.)
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GA02
Two inch TAMU Facilities and Planning aluminum
disk driven onto a 60-inch long piece of 3/8
rebar, driven flush to the ground. It is located
on the southern end of Bizzell St approximately
20 m south from the center of the intersection
with the loop and approximately 12 m north of a
tree. The cap is stamped GA02 1999.
Close-up of point cap
High vehicle traffic, pedestrian traffic
possible. Busy parking lot nearby.
This point may have been disturbed by nearby
re-landscaping projects in recent years.

• Looking northwest to Bizzell St

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S003
High vehicle traffic, little pedestrian traffic.
Pull-off area available during all weathers.
Close-up of point
Looking northwest at University and Bizzell St.
Located on concrete support of sewer manhole
labeled with metal tag S3, at corner of
University and S College/Bizzell. Monument is a
triangle with a central indentation chiseled into
the concrete.
Sanitary sewer manhole
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BACKSIGHT (BS) A GRADE ROD READING TO A POINT OF
KNOWN ELEVATION IN ORDER TO ESTABLISH THE
ELEVATION OF THE LINE OF SIGHT OF THE
INSTRUMENT THIS IS ALWAYS THE FIRST READING
TAKEN ON A LEVELING SURVEY
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HEIGHT OF INSTRUMENT (HI) THE ELEVATION OF THE
LINE OF SIGHT ELEVATION OF KNOWN POINT BS HI
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INTERMEDIATE FORESIGHT (IS) A GRADE ROD READING
TAKEN AT ANY POINT WHERE THE ELEVATION IS
REQUIRED HI IS ELEVATION
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FORESIGHT(FS) THIS IS THE LAST GRADE ROD
READING TAKEN BEFORE THE INSTRUMENT IS MOVED TO
A NEW LOCATION OR AT THE END OF A SURVEY. IF
THE POINT BEING MEASURED AS A FORESIGHT BECOMES
THE BACKSIGHT FOR THE NEXT SET UP IT IS CALLED A
TURNING POINT (TP) HI FS ELEVATION OF TP
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RECORDING READINGS IN FIELD BOOKELEV BS
HI223.28 4.86 228.14 FT
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INTERMEDIATE SIGHTSHI IS ELEV.228.14
4.63 223.51 FT228.14 5.07 223.07 FT
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FOREWARD SIGHTHI FS ELEV.228.14 4.92
223.22 FT POINT D IS A TURNING POINT
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BACKSIGHT TO D (TP)ELEV BS HI 223.22
3.92 227.14 FT
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INTERMEDIATE SIGHTSHI IS ELEV.227.14
3.02 224.12 FT228.14 2.42 224.72 FT
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FINAL FORESIGHTHI FS ELEV.227.14 1.87
225.27 FT
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MATH CHECKALWAYS PERFORM A MATH CHECK!?BS -
?FS LAST ELEV. -START ELEV.8.78 6. 79
1.99225.27 223.28 1.99