Surveying Using the Old and New
Construction surveying on a busy corridor is always a challenge. There is the frustration of trying to stake points through a constant stream of obstructions. Whether it is the contractor’s equipment, parked vehicles or just the daily flow of traffic, maintaining line of sight can be a constant battle. Another problem is maintaining usable control throughout the project. Currently H&AI is the construction surveyor for a road improvement project on a major arterial in north KingCounty. The shape of this project is long and narrow which makes the site a perfect layout for the aforementioned conditions to occur.
Based on these site conditions H&AI field crew came up with a plan to incorporate old technology with new. Using Real Time Kinematic (RTK) satellite navigation, Global Positioning Systems (GPS) and spirit leveling our crews have been able to avoid the fight of obstructions. The key to this plan was setting multiple benchmarks in places that would last throughout the project’s duration. Since elevation is the “weak link” in RTK staking and this site has minimal grade changes, grading was done using a Lenker Rod. This allowed for direct elevations on staked hubs.
Using RTK staking also allowed H&AI to save on man power when staking items that didn’t need to be graded. Staking of saw-cut and right of way lines was done using a one-man crew. And since these items mimic the site shape, the staking was done without changing setups. Our survey methods created significant savings for the client.