N6 Galway City Transport Project

Scope

Topographic Survey and Underground Utility Survey of the preferred route corridor for the N6 Galway City Transport Project.

Survey area of approximately 20km in length and up to 200m in width, requiring a team of approximately 20 surveyors on site to achieve tight deadlines.

The survey area included farmland covering approximately 800 acres, as well as protected ecological areas that required careful attention.

The main route corridor extended from the M6 Motorway to the east of Galway city to the R336 at Barna to the west, various other roads and infrastructure were also surveyed, including national roads such as the N6, N17, N84, and N59.

To ensure safe and efficient traffic management during the survey, comprehensive plans were implemented according to Chapter 8 of the Traffic Signs Manual.

Furthermore, private property, gardens, and businesses within the survey area required liaising with landowners to obtain access permissions.

Topographic Survey

• Survey Control established using STATIC GNSS with stations levelled using digital level and staff.

• Large quarry surveyed.

• Large areas of NUIG surveyed.

• Briarhill/ Ballybrit industrial area surveyed.

• Drains, rivers and bridges surveyed.

• Terrain surveyed included green field/ agricultural lands, NUIG, quarry, M6 Motorway, 4 national roads and many regional roads.

• Structures surveyed included bridges, weirs and culverts.

• Street furniture surveyed such as road signs, traffic lights and street lights.

• Services surveyed such as inspection covers, manholes, utility inspection boxes and overhead lines.

• Road markings surveyed such as arrows, carriageway lines and yellow box junctions.

• Spot heights observed in a 10m grid with all noticeable changes in gradients, depressions and slopes surveyed as separate string lines.

  Underground Utility Survey

• Above ground utilities were surveyed using a combination of GPS and Total Station techniques, which allowed for accurate location and measurement of overhead lines, inspection covers, inspection boxes, and utility poles.

• Below ground utilities were detected using a variety of techniques including Radio Detection, Electromagnetic, and Ground Penetrating Radar (GPR) methods. These techniques enabled the detection of electric cables, telecommunication cables, gas mains, water mains, storm drains, foul sewers, and non-metallic pipes and ducting.

• Utility chambers inspected to create a comprehensive Manhole Description Report which included the utility type, chamber dimensions, depth of pipes/ ducting and diameter of pipes/ ducting.