Masterton - Tomlinson and Carruthers Surveyors Ltd

Background/Project Summary

New Zealand firm Tomlinson and Carruthers Surveyors Ltd has been in operation for over 55 years. It operates in the Wairarapa region (approximately 100km north-east of Wellington) and covers a radius of about 150km around its Masterton office.

Traditionally, cadastral surveying has been the firm’s main focus but in recent times Tomlinson and Carruthers has branched out into more extensive roading, engineering and subdivision designs.

Surveyor Derek Roberts said, “I think the engineering design work we’re now doing is increasing due to a buoyant and expanding industry, combined with new staff and a new curriculum in the New Zealand Surveying degree that has covered changing technology such as using 12d Model and GPS.”

“For example, 12d Model was used extensively on a recent project in the northern end of Masterton, near a big roundabout on the way out of town. The land concerned is known as ‘the horseshoe’, which was part of a significant local car park.”

The Challenge

“The project started as a straightforward two-lot subdivision to provide a council-owned car park with the balance remaining in private ownership. On closer inspection it was found that a larger than normal percentage of the land was actually being utilised as road. To formalise the situation these areas were vested as road in the ownership of the Local District Council. The back of the footpath was used to define the inside lot boundary with the outside being the existing Certificate of Title boundary (road carriageway). In conjunction with this, to the south-west there is part of a river with an open stream flowing through the area. The stream actually forms a natural boundary which we picked up to be compared with the underlying data in preparation for a future project.”

The Solution

“We did absolutely everything in 12d for this job, including creating all cadastral data, design, CAD and plotting. We started by creating our scheme plan (plan of proposal) in 12d which was plotted out and used as part of the application, and then survey pre-calcs were completed within 12d before visiting the site. This information was uploaded into the GPS unit directly from 12d, so when on site we were able to walk directly onto these marks via coordinates rather than having to use conventional methods. This in particular has meant a huge saving in time and also given us a different approach to the majority of our jobs.”

“The information gathered by GPS and also conventional instruments was then downloaded into 12d Model. This data was used to form the basis of the 12d traverse spread sheets through which the majority of the linework for the title and survey plans was prepared and submitted on A2 litho paper. As this project was done using GPS, we also had to use the transformation functions to work out and apply the appropriate scale factors. Using GPS combined with 12d Model’s interface for processing pre- and post-data has probably halved the time required on site. A project of this nature would take approximately two weeks’ worth of work spread over the different stages, including about three days in the field and five days’ worth of calculations and drafting. This is phenomenal compared with the time it would have taken using conventional methods!”

“For Tomlinson and Carruthers, the major benefits of using 12d on this and similar projects have come from the 12d traverse spread sheet – in particular the way it does all the line work, point symbols and annotation of the plan all at once. This has the advantage over other software because 12d is able to calculate and annotate the true information rather than just the projected information.”

The Result

“Once the information is in the 12d traverse spread sheet, the drafting is done automatically. This means the potential for human error – which occurs mainly with reading and writing at the different stages – is kept to a minimum while the whole process is simplified and sped up. We are finding that using 12d Model in conjunction with GPS is saving us around 30-50% of our time spent on this and other projects. 12d’s ability to reduce errors has served us well, particularly with the use of GPS and electronic data recorders. Though you can never beat independent checks, the Traverse Spread Sheet Drafting has removed one of the more difficult areas to police.”

“Luckily, we have found that the training curve for 12d is very small, even for those with minimal CAD experience. For new users of 12d, probably half the learning time has been spent gaining an understanding of survey calculation methods rather than of 12d itself. Ease of learning was particularly facilitated by the ability to set up default files and screens to standardise procedures throughout the office and the whole firm.”

“Being a former SDR Map user, I found the 12d traverse spread sheet very appealing and easy to use overall. 12d has really revolutionised our methods and our approach to the majority of our projects!”