DAI, implementer of the USAID funded Appui à la Valorisation du Potentiel Agricole du Nord, à la Sécurité Economique et Environnementale (AVANSE) project in HAITI, invites qualified vendors to submit quotations to supply and deliver Rivers Physical Survey / Cross Sections.

Attachment C: SCOPE OF WORK
1. X-Section Locations - Four (4) Rivers – Plaine du Nord
a. Haut de Cap River, 17 km, 16 X-Sections
b. Grande Riviere du Nord, 26 km, 26 X-Sections
c. Trou du Nord, 14 km, 16 X-Sections
d. Marion River, 12 km, 16 X-Sections
74 Total X-Sections
e. DAIAVANSE Manager will show Surveyor where 1st X-Section is;
f. Next and following X-Sections shall be equidistant downstream from the previous one so as to achieve the total number shown above;
g. For estimating purposes, assume each X-Section line is 50 m across the river and 200 m each side past the top of each River bank; and
h. Start work upstream, travel downstream.

2. Survey Specification
a. Nomenclature: Each X-Section will be designated by numbers, with the first three capitalized letter of the river and then the following… X01 - X25 (Examples: GRAX001, MONX22, etc.)

b. Elevation Points: Each X-Section shall consist of a minimum 20 elevation points (if the surveyor deems it can be done well with less than 20, please inform the DAI/AVANSE Manager for confirmation)

c. Elevation Control Points: Each X-Section shall have one Elevation Control Point at the end of the X-section that shall be marked with a 750 mm #6 rebar driven into the ground with 100mm showing and painted day glow pink. Each marker shall also have two permanent reference points. Each marker/control point shall have a diagram that shows the reference points (tree, pole, rock) and the chained distance to the point.
Each control point shall be referenced to a master control point (TBM) on each river. Make one Control Point on Each River a Temporary Bench Mark (TBM)
d. Bearing of Each X-Section: Each X-section shall be normal (perpendicular) to the flow of the river. This judgement will be by eye. The Surveyor shall do their best to make the cross section 90 degrees to the flow in the river. Each X-section then shall have a bearing. Surveyor shall record such bearing angle from true north or some other acceptable reference bearing.

e. Typical X-Section: See attached diagram (not to scale). Surveyor shall record the elevation for each point. Note that there are six points where surveyor shall record specific elevations and provide written notes that show these elevations. Note also that the X-Section shall extend 200 m each side past the top of each river bank.

3. Drawings and Deliverables
a. All X-sections shall be drawn in AutoCad;
b. Google Earth KMZ files
c. ArcGIS File



Survey Standards
1. Accuracy and Closure: DTM Vertical and Horizontal Control / Closure: 95% of all checked horizontal and vertical distance measurements shall be accurate to a 10mm +/- tolerance. All angular error shall be no greater than six (6) +/- seconds. The Consultant shall also provide DAI/AVANSE a proof of survey elevation accuracy.

2. X-Section Control Points and Temporary Bench Marks (one each river): Each river shall have one TBM set in a location as approved by DAI/AVANSE with the idea being to establish the actual elevation of all the cross sections. Therefore this single TBM should be located near another GOH or some project (T)BM whose elevation can be checked if possible. If neither of these are possible, the DAI.AVANSE engineer will direct the surveyor where to locate this TBM.

Each X-Section elevation control point shall be referenced to the “One River TBM.” Each of these control points and the “One River TBM” will be referenced to two permanent man made or natural permanent reference points for (horizontal control). Each reference shall include a chained distance less than 25 m and a sketch that illustrates how to find or set the TBM and the control point.

3. Drone Topographic Surveys: In the event the survey will be done by a drone with topographic software, Surveyor will outline a plan to DAI/AVANSE for our approval that addresses accuracy and marker requirements.

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