Peace Project Water Use Plan. Williston Air Photos and DEM. Reference: GMSWORKS-14. Williston Air Photos and DEM

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1 Peace Project Water Use Plan Williston Air Photos and DEM Reference: GMSWORKS-14 Williston Air Photos and DEM Study Period: May 2009 to November 2010 Les Giles Transmission Engineering, Photogrammetry Services BC Hydro 6911 Southpoint Dr. Burnaby, BC V3N4X8 December 9, 2010

2 Williston Reservoir Aerial Photos & Digital Elevation Model 2010 Project Report Introduction The Williston Reservoir Air Photos and DEM project is a supporting project to physical works and monitoring projects within the Peace Water License Requirements (WLR) program. The spatial data collected as part of this project will be used as supplementary data for wetland enhancement, tributary enhancement, dust control, and debris management. In addition to use within WLR projects, the data is likely to benefit various users within BC Hydro as existing spatial data on Williston Reservoir were incomplete. This project will acquire data over a 10-year period. This report describes the first of three sets of air photo acquisition and related photogrammetry work. The project in 2009/2010 consisted of three components: i. Bibliography of a photo/maps for the Williston Reservoir area ii. Aerial photos at a 1:5000 and 1:20000 scale (or digital equivalent) iii. LIDAR and a bare earth digital elevation model Methodology i. Bibliography BC Hydro Photogrammetry Services inventoried BC Hydro s existing collection of maps and photos. A bibliography was then created that included the following information: Film type Film roll number Spatial scale Date of data collection Description of the target area Location of map Owner ii. Air Photos and Related Photogrammetry Aerial photography of Williston Reservoir was acquired by Groupe Alta at a scale of 1:20000 and 1:5000. The 1:20000 scale photos were obtained using a digital sensor and an analog (film-based) sensor was used for the 1:5000 scale photos. In both cases, the data was collected according to the BC Hydro Photogrammetry Services Aerial Photography Specification AP (Appendix 1) and in accordance to BC Government specifications (Appendix 3). One exception to these specifications was the minimum solar angle. Pre-flight discussions between BC Hydro and Groupe Alta resulted in a reduction in the solar angle minimum from 35 to 32 degrees to allow more time per day for photo acquisition. BC Hydro supplied fully-prepared hard-copy and/or digital flight maps and flying heights (approximately 5000 feet above sea level for the 1:5000 scale photography and approximately 14,000 feet above sea level for the 1:20000 scale photography) to Groupe Alta. Groupe Alta provided BC Hydro with an internet site to monitor progress of air photo and LiDAR capture which they updated daily during the mission. Scanning of film photography was completed at a resolution of 14 microns. Aerial triangulation, a process that allows for the spatial positions of all points on an aerial photograph to be mapped precisely, was completed on all photography and adjusted to surveyed ground control points. BC Hydro utilized 53 previously surveyed control points and 1

3 Groupe Alta surveyed an additional 45 control points prior to the photo capture. Orthophotos were generated from the two sets of imagery. Each set of orthophotos were controlled using the LiDAR data set, and were produced to the area encompassed by the 200 metre full pool line. Groupe Alta performed QA/QC at each stage of the process and BC Hydro Photogrammetry Services acted as a secondary check ensuring the quality of the deliverables met all specifications. iii. LIDAR and Bare Earth Digital Elevation Model LiDAR data capture was conducted to BC Hydro accepted standards (Appendix 2) of a minimum of 4 points per square metre, and relative horizontal accuracy of 0.15m and vertical accuracy of.15 m in order for the data set to be used to create 0.5 m. contours. Quality control by Groupe Alta was undertaken both in the field and in the office. Quality control in the field included calibration to target sites at the beginning and end of each day and a validation site was captured at the beginning and end of the mission to verify consistency of the data set. Groupe Alta used computer software to assist in quality control in the office. The aerial photography control sites were verified and compared in the LiDAR data set to keep horizontal and vertical consistency with the photography. Ground classification of the full LiDAR data set was completed and a bare earth data set was extracted and delivered in files of 1 km 2 tiles, along with an index file. iv. Additional Mapping Natural and man-made features were compiled from the aerial photography from the waterline to 200 m (horizontal distance) of full pool. This was accomplished using DVP (Digital Video Plotter) photogrammetric softcopy workstations and provided in Microstation file format. The data was used to augment the LiDAR data set for creation of contours. Results i. Bibliography A comprehensive bibliography was created for all of BC Hydro s maps and photos of the Williston Reservoir. The bibliography is in MS Excel format and includes a list of 630 maps and 64 rolls of film. The BC Hydro Photogrammetry Services maintains and stores the bibliography. ii. Air Photos and Related Photogrammetry Data capture occurred between May 21, 2009 and June 4, 2009 inclusive and resulted in the following: High level (1:20000) digital photos: 1125 from 3 days of capture Low level (1:5000) film photos: 7940 from 22 rolls in 9 days of capture Delivery of the photo data occurred in a staged process with the negatives and digital raw images delivered by July 31, An orthophoto data set was created from the aerial photography and used the LiDAR data as control of the orthophoto, providing a very high resolution and comprehensive data set. The orthophoto created from the high level photos was delivered in April 2010 and the low level orthophoto was delivered in May Both sets of data were broken into 1 km x 1 km tiles (2620 tiles) for ease of viewing and an index in Microstation and PDF formats was included. 2

4 iii. LIDAR and Bare Earth Digital Elevation Model LiDAR data was captured during the same time frame as the air photos and resulted in 2620 tiles of data for a total of 71.5 gigabytes of LiDAR data or approximately 1.5 billion points. LiDAR files were delivered in December BC Hydro Photogrammetry Services conducted quality assurance on the LiDAR files by viewing sample data in 3D Photogrammetric workstations; the data was found to be consistent with RFP requirements. The complete LiDAR Bare Earth data set, delivered by Groupe Alta, included water returns. To avoid confusion in users of the data set, BC Hydro removed most of the water returns by using an FME software routine to eliminate the points inside of the reservoir line. iv. Additional Mapping In June 2010, Groupe Alta provided vector data of man-made and natural features (all visible roads, all visible water features including marshes, swamps, ponds, rivers, etc.) from the water line to 200 m horizontal distance from full pool. The vector data was used along with the LiDAR data to create the contours for the final mapping product. BC Hydro Photogrammetry Services created 475 maps at a scale of 1:2500 and includes an orthophoto background to provide a comprehensive set of maps for the Williston Reservoir. 3

5 Appendix 1 4

6 proud of our Service B.C. Hydro Photogrammetry Services Aerial Photography Specification SPEC. NO. AP December

7 1.0 GENERAL 1.1 RESPONSE TO INVITATIONS Quotations shall be in Canadian dollars and shall include all applicable taxes Firm quotations shall be provided in writing for providing annotated and checked negatives plus an index for each aerial photo project. Quotations shall include all costs including aircraft and crew, ferrying, film, developing, photo index preparation and delivery. 1.2 STANDARDS AND ACCEPTANCE Vendor selection will be made on the basis of cost, availability, and B.C. Hydro s assessment of the technical suitability of each proposal. The lowest quote(s) therefore may not be accepted Except where otherwise noted below, all workmanship and materials shall meet the standards defined in the document Specifications for Aerial Photography. Located at These standards shall hereinafter be referred to as the Photo Standards All work, materials and flight records shall be available to B.C. Hydro upon request B.C. Hydro reserves the right to reject any materials or workmanship that in their opinion does not meet photo standards and/or the conditions otherwise stated in this document Vendors will ensure that appropriate quality control and inspection measures are in place to provide timely delivery of product that fully conforms to this specification. All deliverables shall be provided to B.C. Hydro within ten (10) working days of photo completion Any information about possible and/or noted sub-standard product will be communicated to B.C. Hydro as soon as it is discovered to facilitate timely, informed decisions on appropriate further action Any required re-flights will be given top priority and every effort will be made to secure any requisite re-flights in the same aerial photo season The successful bidder will be informed by a representative of B.C. Hydro Photogrammetry Services a minimum of twenty-one (21) days before the required completion date for each project. Failure to meet the required photography completion date without valid reason will be interpreted as a breach of contract Notwithstanding paragraph above, there may be urgent circumstances when 21 days lead-time cannot be provided. In such cases, the contractors will be informed of the urgency for the work and will respond accordingly. 6

8 2.0 AERIAL PHOTOGRAPHY 2.1 TIME OF PHOTOGRAPHY In general, aerial photography will be secured when the ground is completely free of snow. Timing of projects not requiring that this condition be adhered to will be governed by items and only Photography shall be taken when the solar altitude is greater than thirty-five (35) degrees. No variation from this will be accepted without prior consent of a senior representative of the B.C. Hydro Photogrammetry Services When photo capture extends over more than one day, every effort shall be made to secure photo at similar time and sun angle. 2.2 AERIAL FILM For projects requiring natural color photography, Kodak Aero negative film, emulsion 2445 shall be used (or equivalent) For projects requiring black and white photography, Agfa Ariphot Pan 150 or 200 film or Kodak 2405 film shall be used (or equivalent) The vendor shall provide B.C. Hydro with the developed and annotated films(s) of each project. Annotation of each exposure shall include roll number, exposure number, nominal photo scale, and date of photo The vendor shall provide indices at 1:50,000 scale or larger, (digital format is acceptable) The data strip outside the image frame shall appear on all exposures of the film. 2.3 AERIAL CAMERA All exposures shall be taken using a 23cm. x 23cm. format, forward motion compensating (FMC), metric quality aerial photography camera such as a Leica RC20. Projects not requiring FMC will be noted The camera(s) used shall have current NRC Category A or USGS certification. All calibration data shall be made available to B.C. Hydro The required focal length(s) for each job will be specified by B.C. Hydro Digital Cameras shall be calibrated and meet standards as noted above, and should be of frame type format. 2.4 PHOTOGRAPHY MISSIONS 7

9 2.4.1 Flight maps and data sheets showing required flight lines, flying heights, type of film required, and any other data pertinent to the aerial photo project will be provided to the successful bidder by B.C. Hydro Photogrammetry Services The forward overlap in the line of flight shall be 60% (+/- 5%) unless otherwise stated The side overlap between adjacent lines shall be as per B.C. Hydro s flight lines All flight deviations shall meet the conditions defined by the photo standards. 3.0 SPECIFICATIONS (Reference) 3.1 Refer to current BC Government specifications for guidance. The set of Specifications pertaining to provincial aerial photography are available at this URL: 8

10 Appendix 2 9

11 BC Hydro LiDAR Specifications and Deliverables 1.0 Area to be Surveyed The following areas described by the images below require Lidar Survey. (insert area as required) 2.0 General Specifications 2.1 Flight Operations All flying operations must be performed in accordance with Transport Canada and any special permits or approvals required will be the responsibility of the successful contractor All LiDAR data and imagery for each transmission line must be captured when the entire transmission line is free from snow cover and at a time of day that would minimize the amount of shadow on the right of way. Each response must provide details of the airborne system to be used including aircraft, GPS/INS positioning, flying height, scan angle, ground speed, pulse rate, scan line rate, scan line separation, scan line point separation, laser spot footprint, video cameras and digital still camera. 2.2 Accuracy Requirements. The required relative accuracy standard for all LiDAR and digital video derived measurements is +/-0.15m in X, Y, and Z. The required absolute accuracy is +/- 0.5 metres in X,Y, and Z. All responses must include full details of how this minimal accuracy standard will be achieved for all required deliverables noted below. BC HYDRO or it s approved service provider will provide locations and coordinates of any existing BC HYDRO GPS control points (where available) on or near the transmission rights of way. If BC HYDRO GPS control points exist in the area, then the control points must be used as base stations during the LiDAR acquisition. All data coordinates are to be UTM/NAD83 in the appropriate UTM zone. Where a T/L circuit crosses a UTM zone boundary, all coordinates must be expressed in the UTM zone system in which most of the circuit is located, unless approval is obtained from BC HYDRO or it s approved service provider. 10

12 2.3 Airborne System The airborne LiDAR system used to acquire all data must have the following attributes/capabilities. The LiDAR system must have first / last return and first / last intensity capability with the number of returns reported. The integrated laser should have a pulse rate capability of up to 50kHz and must be able to operate safely at low altitude. Proof of eye safe laser operation shall be provided. The system video data must be able to be used to augment LiDAR data and must have software capable of facilitating accurate measurements and coordinate determination from the video imagery The airborne system must be able to provide automated in-flight recording of meteorological data. Otherwise, an alternate method must be provided. 2.4 Delivery Media Two copies of all final processed data and images for each transmission line will be provided to BC HYDRO on DVD-R. 2.5 Materials To Be Provided by BC HYDRO GPS control point locations and UTM/NAD83 coordinates (where available). MicroStation V8 3-d seed file, resource file and color/level schema. MicroStation V8.dgn file of structure designations/numbers. MicroStation V8.dgn file showing the alignments of the required circuits. 3.0 DATA CAPTURE AND PROCESSING 3.1 Data Capture - Full Swath Flight The LiDAR data will be the source for classified ground, vegetation and cultural features. The digital still imagery will be used for possible future orthophoto creation. 3.2 Data Processing Structure Positions The horizontal and vertical positions of all structures will be determined. Structure position data will include the ground contact point of all poles in a pole structure or all feet of a tower. A calculated structure base centroid position will also be provided for all towers or multi-pole structures. 11

13 3.2.2 Structure Geometry The following structure geometry details will be provided in BC HYDRO specified data format in both ASCII and MicroStationV8.dgn file formats: Structure numbers will be provided by BC HYDRO and are required to be part of the ASCII file records for structure positions and geometry and to be graphic-grouped with the structure positions and geometry in MicroStation V8.dgn file ) Data File Type Summary All data shall be provided in separate space-delimited, ASCII files (X,Y,Z), i.e. structures, attachment points, catenaries, ground, vegetation, etc. All structure/pole positions, structure designations/numbers, structure geometry, all conductor/wire catenaries and the video track plots shall be provided in single MicroStation V8.dgn file. All surface/feature classified data shall also be provided in.bin format Meteorological Data The MET data will be captured continuously and simultaneously with the LiDAR capture of the conductor data either by an automated, in-flight system or by an alternative method that would provide a minimum of one observation within each span of transmission line. Any alternate method for MET collection will be described in detail. In-flight system observations must not be more than 50 metres above the elevation of the transmission conductors. All MET data will be time-stamped to facilitate geo-referencing. The following MET data will be provided in an.xls file for each observation: Circuit number Date Julian day UTM zone X, Y, Z (Easting, Northing & Elevation) of observation Ambient Temperature, degrees C. Wind direction, degrees True Wind speed, kph Time, local Sky condition (S / normal sunshine, R / full cloud, F / full sun, C / polluted atmosphere, hazy) 3.3 LiDAR Surface/Feature Classification All data classifications must satisfy the requisite minimum +/-0.15 metre relative accuracy requirement in all combinations of terrain irregularity and vegetation cover. All classified data will be delivered in ASCII format as well as a.bin format for use with TerraScan Viewer software. 12

14 3.3.1 Classification of Lidar Data LiDAR data will be classified into the following categories: - Ground the minimum ground data point density will be 4 points per sq. metre within the primary transmission right of way. Any areas of ground deemed deficient due to insufficient penetration of vegetation by LiDAR, e.g. heavy timber stands along ROW edge, shall be reported - Vegetation all vegetation within the requisite full swath - Buildings - Highways - Roads paved - Roads unpaved - Driveways - Railroads - Waterways - Non-permanent, moveable features on right of way, e.g. parked vehicles, trailers, debris, hay bales, etc. - Boulders greater than 1 metre square in area within the cleared right of way 4.4 Ground Deliverables Space de-limited x y z ASCII data file with a CSV extension. The ASCII data will be derived from LiDAR data and contain coordinates of classified points. The delivery will include: Ground as classified by the proponent. Options: Model Keypoints (thinned ground as classified by proponent). Please explain how the ground will be thinned to represent the terrain and to meet the accuracy requirements Model Key Points are a thinned set of ground points, selected from the data set by extracting the minimum number of point required to accurately define the surface model. The purpose of model key points is to generate a more manageable file size without compromising the accuracy derived from the original data Fixed Grids (1m,2m, 5m, etc.) Data Accuracy: The relative accuracy of the positional data for structure/element positions will be +/ m. in X,Y,Z components. Relative meaning element to element of a structure and structure to structure of a span. The absolute accuracy will meet or exceed the +/- 0.5 m. specifications. 4.5 Vegetation Deliverables Space de-limited x y z ASCII data file with a CSV extension. The ASCII data will be derived from LiDAR data and contain coordinates of classified points. The delivery will include: 13

15 Any vegetation that is not included in the buffer zone, which is defined by Low Vegetation Any remaining data that has not been classified as Ground, TL Conductor, Underbuilt Wires, or Structures will be considered Medium Vegetation - All data remaining that has not been specifically classified The delivery will not include: Low Vegetation - This class represents data that is buffered between the ground and medium vegetation (a BC HYDRO defined distance). Eg shrubs, grass, etc. 4.6 Structure Data Deliverables The delivery will be a Microstation V.8 design element indicating x,y,z, structure type, structure #,circuit # (see design file specifications) and space de-limited x y z ASCII data file with a CSV extension. The ASCII data derived from the design file will contain coordinates of center of cell as well as structure type. The ASCII data derived from LiDAR data will contain coordinates of classified points. The delivery will include: LiDAR TL Conductor structures and points of attachment A text string in the design file as described above. CSV file containing xyz and structure type XYZ for all pole locations at their bases XYZ for all centroid ground locations of 4 footed towers A separate ascii file will be delivered that includes the centroids of each structure as defined below: For a four footed structure the centroid will be calculated from the four feet, the Height (z) will be derived from the ground DTM model. For a 3 pole structure the base of the middle pole will be considered the centroid. For a 2 pole structure the centroid will be calculated as the mean between the 2 pole bases and a Height (z) will be dervied for the x,y of the centroid from the DTM model. For a 1 pole structure or single guy structure the base of the structure will be considered the centroid. Labels (Structure Names) will be added as annotation when possible. 7.0 QUALITY ASSURANCE The successful contractor will be required to deliver data that fully conforms with BC HYDRO s specifications. BC HYDRO reserves the right to reject any data that in their opinion that does not meet requisite specifications. No payment will be made for unsatisfactory data. BC HYDRO also reserves the right to cancel (at any time) contracts with any contractor who delivers substandard data. Responses to this RFP shall provide details of contractor quality assurance processes and explain how these processes will ensure that required specifications will be satisfied. 14

16 8.0 DELIVERY Below are listed the Deliveries required for data that must be completed as per the schedule presented in item Bare Earth ground model General Notes MPEGs Video clips will be created from the nadir and forward tapes for each circuit Every effort will be made to omit any overlap in the final product. Cell Library All cell libraries and or cells required will be as supplied by BC HYDRO. 15

17 Glossary of Terms Transmission Lines Moves electricity from generating stations to distribution substations where it is transformed to lower voltages for distribution to customers. The high voltage transmission system consists of transmission lines operating at voltages from 60kV to 500kV Distribution Lines Wires used for transporting small amounts of power from a distributing station or a regional supply center to the customer s local transformer. Voltages for these wires can be as high as 34.5kV but are usually below 13.8kV. Other Wires Currently defined as any wire that does not attach to, and is no way related to the principle circuit and/or its structure, or has not been defined by current definitions described in this document. Point Of Attachment Where 2 catenaries join together at a structure or a single catenary connects to the structure. The later could also connect to a conductor insulator at the structure. Potheads This is the pole location when the conductors go underground Shield Wires Are generally located at points of the circuit that are prone to lightening strikes and rarely cover the entire circuit. Station A concentration of electrical equipment provided to fulfill a specific function on the electrical power system. For example, a generating station(gs), transformer station(ts), switching station(ss), or distribution station(ds). Many utilities describe all stations except generating stations as substations. Substations see Station Underbuilt Wires Wires that are connected to the principle circuit structure. These could include other circuits, distributions wires, tap wires, tv cable, fibre optic,etc. Underbuilt Crossing Wires Are wires that cross under the principle circuit but do not attach to its structure. 16

18 Sample Delivery Data Meteorolical Data Circuit Date Day UTM Zone Northing Easting Elevation Temp Wind Direction Wind Speed Time Sky Condition m. Deg. C. Deg. True Kph PST F - sunny/clear 5L30 Feb. 05/ :25:03 F - sunny/clear 5L30 Feb. 05/ :27:00 F - sunny/clear 5L30 Feb. 05/ :31:28 F - sunny/clear 5L30 Feb. 05/ :35:00 F - sunny/clear 5L30 Feb. 05/ :41:21 F - sunny/clear 5L30 Feb. 05/ :48:52 F - sunny/clear 5L30 Feb. 05/ :55:03 F - sunny/clear Ground, Vegetation, Wires, TL Structures, Encroachment, And Buidings CSV File Sample File Naming Circuit #_v7.dgn Circuit #_TL_Conductor.csv Circuit #_UB_Wire.csv Circuit #_UB_Crossing.cvs Circuit #_Shield_Wire.csv Circuit #_ground.cvs Circuit #_vegetation.csv Circuit #_TL_Structure.csv Circuit #_Encroachment.csv Poa and Poles Sample File Naming Circuit #_POAs_and_Poles.csv cntid

19 Appendix 3 18