Common use of Project Horizontal and Vertical Control Clause in Contracts

Project Horizontal and Vertical Control. a) The Horizontal and Vertical Control for this project shall be based on the same datum, basis of bearing, calibration and benchmark as used for the Aerial Survey. b) Horizontal Control Shall be based on the CCS83 Zone 6, 1991.35 epoch, U.S. Survey Feet per ROS 14492. It is required to tie into a first order monument per ROS 14492 unless a first order monument no longer exists within a three mile radius. c) Vertical Control shall be based on NGVD29 per benchmarks in the City of San Diego Bench Book. Non 1970 adjusted and 1970 adjusted benchmarks listed with an asterisk (*) in the City Benchmark book are not to be used together for Vertical Control – common adjustment sets are to be used. d) If adjacent City projects have been found and are included in the research packages, measurements to a minimum of 3 common control or ROW points shall be made for evaluation and consistency between projects. These projects can be used for establishing common horizontal or vertical control, joining or adding to existing data, and/or as an inventory of survey monuments for search purposes.