Law Summary
Scope
- Covers the transformation and integration of all cadastral data into PRS92
- Includes database management mechanisms for transformed datasets
Key Definitions
- Adjusted Coordinates: PRS92 coordinates after transformation
- Analog Data: Traditional paper maps and records
- Cadastral Data: Records of cadastral and isolated surveys
- Cadastral Database: Organized geo-referenced digital data managed by Land Management Bureau/Services
- Cadastral Map: Map showing land parcels and features for ownership documentation
- Cadastral Survey Projects: Extensive municipality or city-wide surveys
- Control Points: Known coordinates used as survey reference points
- Conversion: Digitizing analog data
- Digital Data: Electronically recorded information
- Global Navigation Satellite System (GNSS): Satellite-based positioning system
- Graphical Cadastre: Survey using graphical methods
- Integration: Consolidating data into PRS92
- Local Transformation Parameters: Constants for coordinate transformation to PRS92
- Metadata: Structured data describing features
- Numerical Cadastre: Survey based on ground measurements
- PRS92: National coordinate reference system
- Residual: Difference between observed and computed coordinates
- Source Map: Maps used in cadastral data conversion
- Transformation: Converting spatial data between coordinate systems
- WGS84: Global earth-centered reference frame
Cadastral Data Conversion Process
- Conversion begins with lot corners, survey controls, and reference points
- Primary data sources: lot computation sheets, lot description sheets, field notes, monument descriptions, boundary maps
- Conversion order: lot data computation sheets, then lot description sheets, then reconstruct from field notes if necessary
- Resurvey required if data unavailable after exhaustive search
Inventory of Records
- Conduct thorough inventory of cadastral records by regional offices
- Assess completeness and quality for integration into PRS92
Conversion of Coordinates
- Use Philippine Plane Coordinate System — Transverse Mercator/Luzon 1911 (PPCS-TM/Luzon 1911)
- Convert Local Plane Coordinate System (LPCS) data to PPCS-TM/Luzon 1911 as required
Encoding Coordinates and Data
- Use customized databases and spreadsheets to encode project controls, reference points, and individual lot corners
- Check bearings and distances against technical descriptions
Reconstruction and Resurvey
- Reconstruct lot computations and descriptions from original field notes if necessary
- Conduct PRS92-compliant resurvey for missing/unavailable data after thorough data search
- Resurvey graphical cadastre lots with PRS92 referencing
Standardization and Quality Control
- Follow standard encoding conventions for data uniformity
- Regional offices ensure data integrity, note errors for remedies
- Correct discrepancies in untitled parcels administratively; titled parcels through courts
Adoption of Converted Coordinates
- Adopt converted parcel coordinates as official data
- Note discrepancies for future remedy
Digital Plotting and Database Setup
- Use CAD/GIS software to project coordinates and create digital cadastral and index maps
- Establish and maintain digital cadastral database including maps, descriptions, sketches, and remarks
Recovery and Observation of Control Points
- Composite Survey Teams recover control and reference points including additional points near municipal boundaries
- Prepare monument recovery reports and schemes for evaluation
- Select sufficient recovered points for GNSS observation based on distribution and condition
- Alternative use of lot corners for transformation if control points insufficient
- Survey using authorized persons under RAs 8560 and 9200
- Use GNSS or conventional surveying techniques referenced to PRS92 controls
Survey Reporting and Approval
- Submit detailed reports including monument statuses, recovery sheets, methodology, and observations
- Regional surveys division evaluates and approves control points for transformation
Determination of Local Transformation Parameters
- Compute four-parameters transformation (rotation, scaling, translation) using least squares method
- Apply weights based on point accuracy level
- Analyze residual errors, exclude points with errors >1m
- Iterate until residuals acceptable and parameters stable
Transformation Accuracy Assessment
- NAMRIA and LMB assess transformation accuracy including preliminary check, ground validation, and adjoining project verification
- Validate at least 10 corner points on shared boundaries
- Conduct resurvey if significant errors found
Derivation and Approval of PRS92 Coordinates
- Use computed transformation parameters to derive PRS92 coordinates for all control points
- Submit all relevant data and reports to LMB for approval
- NAMRIA and LMB monitor approval via databases and strategies
Integration and Map Production
- Transform all relevant coordinates into PRS92 for control map creation
- Plot adjacent parcels, verify against existing cadastral maps
- Investigate inconsistencies and submit reports for review and correction
- Regional surveys division recommends approval
Database Management
- Manage cadastral database with loading, merging, backups, restoration, user management, and tuning
- LMB manages national database; LMS manages regional databases
- NAMRIA provides technical support and receives periodic national database copy
- LMB/LMS to issue guidelines consistent with this manual
Updating New Surveys
- New surveys must comply with PRS92
- LMB issues guidelines for inspections and approvals
- Incorporate new data into database, subject to evaluation
Software Tools Provided by NAMRIA
- Templates for converting analog data to digital (coordinates, bearings, distances)
- Tools for calculating local transformation parameters
Metadata and Spatial Data Infrastructure
- NAMRIA develops metadatabase system for cadastral data installed in regional LMS offices
- Provides training to Composite Survey Teams
- Metadata supports creation of Cadastral Spatial Data Infrastructure
Unauthorized Use and Transfer
- Copying or transferring cadastral data without authority is subject to penalties under existing laws
Outsourcing
- Regional LMS offices may outsource data conversion and surveys if internal capacity insufficient
- Cost must not exceed prevailing unit rates
Data Transfer from LMB to LMS
- LMB inventories cadastral data and transfers data (including microfilms, magnetic media) to LMS for conversion
Technical Assistance
- NAMRIA and LMB provide ongoing technical assistance and oversight to LMS
- Develop graphics database to support parameter approval
Task Groups
- NAMRIA and LMB establish task groups to monitor, assist, and ensure program implementation
Penalties
- Violations of the Manual's provisions attract appropriate penalties under existing laws and rules
Amendments
- Supplementary procedures and amendments issued jointly by NAMRIA Administrator and LMB Director
Repealing Clause
- Procedures inconsistent with this Manual are repealed or modified
Effectivity
- Manual is effective immediately