The app appeal: Surveying larger areas within a tight timeframe

Transport September 25, 2020

Daneen Cowling, Assistant Project Manager, ADAS (an RSK company)

One of the biggest problems our clients encounter when conducting environmental surveys is how to accurately survey large areas in a tight timeframe. Particularly when working for large rail clients, we have recognised that time is a critical factor in meeting the requirements of a rapidly expanding UK rail network. Responding to our clients’ needs, we identified the demand for a bespoke survey tool and have been working hard to perfect our app for the last three years. It is now a finely tuned piece of software that has been used on some of the UK’s largest rail projects and is easily transferrable to other purposes.

The bespoke survey tool uses Esri’s Collector app and Survey123 and enables us to create surveys on an interactive map that can be used offline in the field or online on a desktop. To date, this has primarily been used for arboricultural surveys, but it could easily be transferred for use on other surveys, for example, ecological surveys.

The tool enables point data to be collected, which, in the case of arboricultural surveys, is useful in locating single features such as trees. With point data, you get an accurate GPS location and an attribute table to associate with the feature. In relation to trees, we have also been able to apply crown spreads by collecting spread data then using a geoprocessing tool to create the spread polygon around the point.

Spread data (group of trees) and point data (single trees)

Spread data (group of trees) and point data (single trees)

You can also create polylines, an effective way to identify hedges or boundary features. Polylines are useful features to collect, as not only do they record an accurate location, but they can also measure geometries. This means that length can be an automatically calculated field, which increases the accuracy of the data. Surveying a linear feature enables you to trace accurately while on the ground, in addition to using the satellite imagery base map.

A hedge boundary highlighted using polyline

A hedge boundary highlighted using polyline

Similar to polylines, polygons enable you to collect accurate geometries that are automatically measured and populated (e.g., area and perimeter length). We have used polygons to collect tree groups and woodlands. The app has been useful in accurately capturing the boundaries of the features. The capture of polygons is very transferable for other survey disciplines and is useful for measuring site boundaries, habitat types and other features that are measurable by area.

A group of trees identified by a polygon

A group of trees identified by a polygon

We have also used Survey123 to capture more detailed woodland surveys. Using additional software, we have created a hyperlink in the Collector app to a more extensive survey form in Survey123. This enables more complex data to be collected that include additional features such as skip logic and on-the-fly calculations. We have used these features to collect information on different woodland stands and plots within the total woodland area.

Using this software has revolutionised the efficiency, accuracy and quality of the surveys we can now carry out. Data can be interactively recorded and validated in the field without the need for spreadsheets, paper maps or a data connection, then uploaded when back online. This innovation has brought significant benefits in the quality of the outputs, the sustainability of the resources required and, ultimately, the reputation of the company as a leading environmental technological innovator.

We are proud to be an innovative business that is responsive to our clients’ needs. In the current climate, with the additional constraints on work owing to the coronavirus pandemic, this is increasingly important. The app, for example, reduces the time and number of people required at the site to undertake the survey. A minimal number of people is required on-site to plot out the site features (often just one is enough) and, once the points have been plotted, most of the work can be done back in the safety of the office (or home office, or anywhere with internet access).

If you would like to find out more about ADAS’s bespoke survey tool, related services and innovations, please contact Ben Hockridge or Daneen Cowling. You can also read ‘The Case for Collector’, the full story map article here.