Surveying & Mapping

Question 1

Are you aware of any professional standards relating to surveying and mapping?

What does it cover?

Answer 1

“Use of GNSS in Land Surveying and Mapping (2023)”

• Outlines the integration and application of GNSS technologies in land surveying and mapping practices.
• Highlights accuracy considerations, and examples of application e.g boundary surveys

Question 2

What are Global Navigation Satellite Systems?

Answer 2

• Network of satellites that broadcast positioning, navigation and timing data

Question 3

What other technologies are there other than GNSS?

Answer 3

• Lidar (light detection and ranging) for topographic maps
• Total stations that measures distances and angles.

Question 4

What is GIS?
(Geographic Information Systems)

When would you use it?

Answer 4

Software that links geographical data with a map and allows users to add layers to show different information

• Google maps to measure rough distances, or google earth to see various perspectives and scales

Question 5

What mapping software do you use and why?

Answer 5

• I use the ‘Flood map for planning service’ on the government website - overlays flood zones over an OS map.

Question 6

How would you set out for piling if not just relying on GIS?

Answer 6

• Need to be precise.
• Would use GNSS = Global Navigational Satellite Systems which in Real time correction can get it down from 20mm. This is good for alignment to edge of road, BUT Setting out works to tolerance of 10-15 mm NEED MORE PRECISION
  –>bring in total station.

Question 7

What are key causes of errors with surveying and mapping/measurement?

Answer 7

• Equipment errors
• Human errors
• Conditions – i.e vegetation with high moisture content can lead to signal loss with GNSS

Question 8

Why is it important that surveying is accurate?

Answer 8

• If for setting out works, the rest of the development is based around these initial measurements.
• = compounded errors down the line

Question 9

How could you reduce errors when surveying?

Answer 9

• Repeatability, checking conditions are suitable and ensuring that equipment is calibrated

Question 11

What would be some key project planning considerations when undertaking a survey?

Answer 11

• Area of interest
• Time of year
• Air traffic control / airspace

Question 12

How can you check that accuracy of measurements?

Answer 12

• Compare them with historic measurements, other maps.