Helping the EA clear dead fish

IWJS were called in last week to assist the EA clear dead fish from a small area of the Norfolk Broads. The current pleasant weather has had the unfortunate side-effect of increasing a buildup of toxic algae which depletes oxygen levels in the water and kills fish.

The algae bloom has been attributed to a mixture of environmental conditions, including salinity and water temperature. It is not known what has caused these conditions to alter so dramatically.

The EA rescued and relocated 230,000 fish last month after they were found shoaling in a shallow haven away from the bloom near Potter Heigham.

A further 110,000 have recently been moved from Somerton, roughly six miles away, and over the weekend another 300,000 fish were moved.

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Contract Win – IWJS go VIP at the festivals

CONTRACT WIN – Servicing major festivals

IWJS have again been awarded the tanker work to remove grey water waste from the VIP and backstage area’s of the summer festivals in the London and surrounding area.

The festivals include V-Festival, Wireless and Latitude as well as a few others.

The staging company told Technical Director Tim Day that the level of service provided over the last 5 years and the understanding of his needs by our operators made it a very simple job for him when deciding to place the order with IWJS again.

deep sewer CCTV survey

UUTS Manchester University Sewer Survey

Project:                     Manchester University Build Over

Client:                       United Utilities Total Solutions Ltd:

End Customer:        Manchester University

Location:                   Materials Science Centre Upper Brook Street, Manchester

CCTV sewer survey

CCTV sewer survey



Project Background:

Manchester University want to construct a new building over a deep United Utilities combined major trunk sewer.

The sewer is a 3.8 diameter Trunk Main located directly beneath the build over site, the precise location needed to be determined prior to any piling and construction works and to ensure the asset was safe from the construction activities.   The sewer is constructed in rock with a brick lining and is up to 18 metres below ground level.    To assist with the build over design a pre-condition survey was required so that UU could approve the design and sanction the construction.    On completion of the build a post construction survey is also required.

Access to the sewer was problematic due to limited access points, depth, multi landings, high flows and side entries.   The sheer size and flow levels also meant conventional crawler mounted CCTV and Man Entry surveys were ruled out.



Stage 1

A recce of all located chambers was undertaken to determine equipment access issues, rescue techniques and the survey method.   Detailed surveys were undertaken of all manholes and landings supported by diagrams and photographs which enabled the RAMS to be prepared and access permits granted.

Stage 2

Following several site meetings with representatives from the University, the construction Design Consultants, United Utilities operational and management staff and IWJS Managers and Supervisors an acceptable method was proposed and eventually accepted once it was vigorously checked by the relevant health and safety departments of all concerned .



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Stage 3

Using a high volume combination unit as a winch device we towed an inflatable raft complete with a CCTV platform and location probe from a number of limited access points over a period of three night shifts.   A four man, high risk confined space entry team were required to position the equipment and inflate the raft below ground using protective sheets to avoid puncturing the floatation device when installing and retrieving it.  The whole project was supported by a six man IWJS Rescue Team complete with BA equipment in case of safety alerts or in sewer incident.

During the survey an above ground mapping team was engaged to locate the sewer using a transmitting sond attached to the raft which was picked up on the surface with an RD7000 radio detection device.   All points marked on the surface were then surveyed using a GPS unit which accurately pin pointed all signals received to enable the sewer route to be created on a CAD drawing.

All works were in accordance with:

  • Confined Spaces Regulations 1997
  • The Management of Health and Safety at work regulations 1999
  • Water Industry act 1991
  • Water Act 2003
  • Flood and Water Act 2010.



Stage 4

Provision of survey report including:

  • Summary of findings
  • Details of all points of interest
  • CCTV recording on DVD

CAD drawing of survey results showing:

  • Points of damage and extent (if known)
  • Points of erosion and extent (if known)
  • Other areas of interest
  • Depth and level recordings

Welcome to our New Website

Finally, we are very pleased to be launching our brand new website in our new colours and using new logo. We hope you will find it informative and easy to use. Over the coming months we will be adding much more content so please keep checking back with us.