SPECIAL PROJECT SPECIFICATION
SECTION 184 - P-LINE SURVEY, EXISTING ROADSApril 10, 1997
DESCRIPTION
184.01 Work. This work consists of the P-line (preliminary line) survey of roads to be
reconstructed, including staking the existing centerline, running traverse, profile, and cross
sections over the line; and recording and submitting all survey data to the Forest Service. The
work includes furnishing all labor, equipment, instruments, materials, transportation, and other
incidentals necessary to complete the work in accordance with these specifications and
acceptable engineering practice.
Accomplish the P-line survey under the direction of a registered professional engineer or land
surveyor as required by applicable State laws. This requirement is waived under the industrial
exemptions of the applicable State laws relating to professional licensing when the work is
performed under a timber sale contract by the timber purchaser's employees.
MATERIALS
184.02 Stakes. Use survey stake sizes as listed herein:
Line Stakes - Use stakes with minimum nominal dimensions of 10 mm x 50 mm x 460 mm and
planed or smooth sawn on the 50 mm faces. Paint the top 50 mm of all stakes fluorescent orange.
Set points in the surface of existing roads with 30-penny spikes or larger, pushed through a 4-fold
loop of plastic tape, which shall protrude at least 75 mm on each side of the spike. Bury spikes at
least 100 mm below surface of road. Offset reference stakes for these points perpendicular to the
points and to the back slope side of the existing road in a position not to be disturbed by road
maintenance activities.
184.03 Survey Note Paper & Books. Use moisture resistant paper for survey notes. Contain
notes in books with covers that will protect the contents and retain the pages in numerical
sequence. Hand calculator/portable data recorder printouts may be accepted in lieu of hand
recorded field notes.
184.04 Government Furnished Information. The Government will furnish the Contractor with
copies of design criteria and available recovery notes to public land survey corners.
SURVEY REQUIREMENTS
184.05 Precision. Precision and accuracy requirements shall be as follows:
Angular Accuracy:1 set, direct/reverse. 1' rejection limit
Distance Accuracy:1/1500
Elevation Accuracy:Nearest 45 mm
References to Traverse: 2 adjacent PI's every 300 m, and at the
beginning and end of the survey.
Cross-Section Accuracy:All breaks of 0.6 m or more; slope breaks of 5% or more.
Typical survey instruments to achieve this level of accuracy are transit,
clinometer or abney, steel tape, level and level rod.
184.06 Survey Notes. All notes become the property of the Forest Service. Notes may be
in a format compatible with that used by the Contractor, subject to approval of the Contracting
Officer.
Furnish completely legible manually recorded survey notes. Delete errors by lining out. Record
date, crew names and positions, instrumentation, and weather in the notes at the beginning of
each day's work. The party chief shall sign or initial each page of the notes immediately after
the last entry for each day's work.
Consecutively number electronically recorded survey notes and head to identify the contents.
Include a bound Day Book that records the project name and for each day identifies date,
crew names and positions, instrumentation, weather, type of survey, stationing of sections
between which survey was performed, and survey data or sketches that cannot be electronically
recorded with the notes. The party chief shall sign or initial the electronically recorded notes and
Day Book immediately after the last entry for each day's work.
184.07 P-Line Staking. Mark the beginning and ending of the area to be surveyed on the ground
with flagging. Establish the P-line using the existing road centerline as a guide which should
represent the approximate final centerline of the road. Do not deviate the surveyed line from the
existing road centerline more than 1.5 m horizontally. Locate the surveyed line as necessary to
limit deflection angles to not more than 35 degrees, unless otherwise approved by the Contracting
Officer.
Set stakes solidly in the ground at all breaks in grade and adjacent ground profile and at all
existing culverts, existing turnouts, intersections with planned and existing roads, property
boundaries, fence crossings, etc. Measure distances as horizontal distance. The maximum
horizontal distance between stakes shall be 15 m. Mark stakes with the stationing of the point on
the side facing the origin of the survey or the point offset from. Write information on stakes with
a stake pencil that leaves an indentation in the wood or with waterproof ink.
Where the traverse originates at an intersection with an existing road, or intersects with an existing
road, survey 60 m in each direction along the intersecting road centerline. Survey the intersecting
roads in the same manner as that required for the P-Line survey.
Tie the traverses to the P-Line traverse by angle and distance and identify them on the stakes and
in the notes as "Q-lines." Number Q-lines consecutively and record them in a separate book or
note packet for each line.
184.08 Traverse. Measure and record a bearing or azimuth, as directed by the Contracting
Officer, to the nearest one (1) degree along the survey line at the beginning of each survey and
at a maximum interval along the line of 300 m. All traverse angles shall be measured to the
accuracy specified.
184.09 Profile. Use existing benchmarks whenever possible to determine elevations. In the
absence of an existing benchmark, establish a project benchmark at the origin of the survey, at
the intersection of any traverse originating from the survey, and at maximum 300 m intervals
along the traverse line. Set these benchmarks outside of the existing roadway, identify them
by number and elevation, and record the location in the survey notes. Run and close a level
loop on the benchmarks to the required precision.
Determine the ground elevation of each staked traverse point and record the elevations to the
nearest 30 mm. Profile levels may be taken as a part of the control level circuits. Where taken
separately from the control level circuits, close profile levels on the benchmarks within the
required accuracy.
184.10 Cross Sections. Take cross sections at each staked point on the P-line and measure
as percent slope and slope distance. Extend cross sections each side of P-line for a minimum
distance of 15 m slope distance if the ground slope is under 40 percent, 25 m slope distance if
the ground slope is between 40 percent and 55 percent, and 30 m slope distance if the ground
slope is over 55 percent.
Take cross sections along a line perpendicular to the P-line on tangents and bisecting the interior
or exterior angle at PI's (points of intersection).
Take readings along each cross section at each obvious break in ground slope, and at edge of
road, ditch bottom, top of cut, toe of fill, etc. Record slope as positive or negative, as referenced
from the P-line.
Note existing features such as drainage’s, fences, roads, property boundaries, corner posts, etc.
within 30 m slope distance of the P-line and those within or adjacent to the cross section.
MEASUREMENT
184.11 Method. The method of measurement, described in Section 106, will be
DESIGNATED in the SCHEDULE OF ITEMS.
The quantity shall be the number of kilometers, measured to the nearest 10 m, of completed
and accepted survey.
PAYMENT
184.12 Basis. The accepted quantities will be paid for at the contract unit price for each pay
item shown in the SCHEDULE OF ITEMS.
Pay ItemPay Unit
184(01) P-Line Survey, Existing Roads...... Kilometer
184(02) Q-Line Surveys...... Kilometer
R6/SPS 184 P-LINE SURVEY EXISTING ROADS 4/10/97 1