services details

Highways Drainage Surveys

At Crown Plus we offer a full range of drainage surveys to differing specifications dependent upon the Clients requirements. Some of our flagship surveys have included the Highways England Smart Motorways Projects which required all surveys to be undertaken to the HADDMS or IRIS Specification (CD535 formerly HD 43/04, IAN 147/11 & CS551 formerly SD15/03).

These include:

  • Validation surveys
  • Priority Asset surveys
  • All asset condition and connectivity survey
  • Pipework Geometric surveys
  • Filter Drain Condition
    Surveys using 3D GPR
  • Pipework and Chamber defect survey using CCTV methods
  • Quick Asset condition surveys
  • Balancing Pond Surveys

On-site surveys are performed utilising a range of surveying techniques and the latest surveying equipment such as ‘Manhole Laser Scanners’ that negate the need for man entry into manholes and whilst capturing HD imagery that creates a detailed condition survey of the chambers. Upon completion of the surveys the data is checked and processed to produce the required detailed reports, which can include:

  • CCTV survey reports
  • Remediation schedules
  • Connectivity drawings
  • Condition drawings
  • Design drawings
  • 3D Point cloud shapefiles
  • Cleversan node reports
  • Point Asset reports
  • Validated Shapefiles

In 2019 Crown Plus was awarded a place on the North & Mid Wales Truck Road Agent (NMWTRA) Drainage Condition & Connectivity Survey Framework having been ranked in 1st place for both our Quality and Commercial responses. These surveys specialised in ascertaining the location and condition of the existing highway drainage with the use of Quickview Survey Cameras and the post processing of the drainage data for upload into the Integrated Roads Information System (IRIS).

Drainage Surveys

Validation Surveys

We undertake surveys to verify whether the drainage inventory information held on the Drainage Data Management System (DDMS), previously derived from scheme as built drawings, is a true record of the visible surface point assets or not.

Priority Asset Surveys

We undertake detailed surveys in areas where the highway drainage system is unknown or uncertain. The purpose of the survey is to locate the outfall or soakaway point of each drainage catchment, together with any culverts passing under the carriageway, to facilitate management of pollution and flooding risk on the highway network.

All Asset Condition and Connectivity Surveys

Our in-house teams routinely undertake all assets condition and connectivity surveys. We undertake the surveys to determine the inventory, asset condition and the connectivity and flow direction of all drainage assets in a drainage system. Initially we undertake a desk study of the area of the network in question and then undertake a walkover of the site accessing chambers where possible. The condition survey is undertaken generally using pole mounted cameras during daytime working hours. The survey works also include the GPS surveying of all chambers and surface water items where they are accessible. All findings are recorded with the data roundtripped with the DDMS drainage system data.

Pipework Geometric Surveys

Geometric surveys are undertaken to determine the internal circumferential geometry of the drainage pipework. We undertake the works by attaching a laser profiler to a conventional CCTV camera with the works undertaken in conjunction with a detailed defect survey.

Filter Drain Condition Surveys by GPR

Over a period of time the effectiveness of the filter drain systems are compromised due to the build-up of sediment. In conjunction with our supply chain partners we undertake filter drain condition surveys to determine the service condition of the filter medium of combined surface and sub-surface drains, and other forms of filter drain, using the very latest 3D ground penetrating radar (GPR) technology. We produce detailed reports showing the depth and extent of siltation. This information can be used to plan maintenance schemes, such as filter drain recycling, and also to predict when intervention may be required to prevent a flooding event.

Alongside these works we also undertake site investigation works that enables soil samples to be obtained for the purposed of waste classification and quantification.

Pipework and Chamber Defect Surveys using CCTV

We undertake pipework and chambers defect surveys to determine the inventory, condition and detailed defects of pipework and the associated chambers and gullies, The surveys are undertaken using a range of surveying equipment such as CCTV and push rod cameras. The purpose of the survey is to obtain a full and detailed knowledge of the condition and defects of the below ground drainage pipework. Generally we are engaged to undertake the surveys because, either;

  1. there is a known problem with the performance of the pipework that needs to be understood; or
  2. there is flooding or defects in other assets that are suspected to be due to defective pipework; or
  3. an all-assets condition and connectivity survey has indicated a structural or service grade of 4 or 5 within the pipework that requires further investigation; or
  4. repair, replacement, or redesign of the drainage system is being investigated; or
  5. for contractual certification of new build drainage works.

We undertake the surveys on all drainage systems up to 900mm in diameter and in culverts up to 1800mm in diameter.

The survey works are proceeded by the in-house jetting and cleansing teams who also use the latest and highly efficient Jetvac recycling units.

Whilst the data is captured, with condition data directly input into existing or new shapefiles, our experienced GIS Engineers undertake QA works and post process the information for upload to HADDMS/IRIS and produce CAD drawings for pre-design/construction and post construction purposes. All drawings and reports are provided in both PDF and electronic formats to suit our clients’ specific requirements.

Quick Asset Condition Surveys

Quick Asset Condition Surveys is a powerful new connectivity survey method that utilises the latest HD camera technology to assess the condition of a pipe.

We can understand the condition of a sewer rapidly and affordably with the cameras across large areas of a drainage network. Using high-powered zoom optics, we can assess manholes, tanks together with sewer lines from an adjoining manhole.

It’s perfectly suited for:

  • Diagnosing emergency call-outs
  • Avoiding confined space entry
  • Conserving CCTV resources
  • Performing a rapid, system-wide assessment
  • Prioritising CCTV, cleaning, and rehab activities
  • Viewing pipes too deteriorated for a traditional CCTV rig

Therefore, we can carry out surveys faster, and offer additional data capture that helps clients manage assets more effectively. This is a valuable and cost-effective alternative to carrying out detailed asset defect surveys. A team of two surveyors can survey up to 1.5 kilometres of highway drainage assets per shift. That compares with no more than 500 metres for a conventional robotic crawler camera team. In turn this reduces the amount of Traffic management required and road space bookings.

As part of the works, we provide a daily tracker to the Clients team identifying the location of any defects that we consider that may cause a significant issue at time    of heavy rainfall. This varies from mass roots, major blockages, collapsed sewers through to blocked headwalls/outfalls. This then allows the client to undertake further detailed investigation works to ascertain the cause of the damage and undertake the timely rectification of the defect.

Assessment and Inspection Surveys of Balancing Ponds

Balancing ponds are a critical asset within any Highways Authorities drainage network. These assets provide critical pollution control and important attenuation capabilities in the event of heavy or prolonged rainfall. We offer a comprehensive survey service for these assets. Topographical surveys are undertaken to accurately map the location of the ponds and all their attributes such as anti-pollution devices, all vital components of a quality report detailing full condition assessment.

In addition, we can calculate the depth of silt in the ponds using sonar surveying technology. The surveys allow the owner to assess the capacity/performance of the asset and plan routine maintenance such as silt/sludge clearance.

All survey data obtained on site is then collated and processed in the office by our team of technicians using the latest CAD and GIS software. A complete report can be prepared for the client along with a fully compliant ESRI SHP File for upload to the HADDMS database if required.