---
title: "Dawdon Short Sea Outfall Repair Works"
ocid: "ocds-b5fd17-c3c71668-0c85-42e1-b5da-9a9f088094c5"
canonical_url: "https://d3tenders.com/contract/?ocid=ocds-b5fd17-c3c71668-0c85-42e1-b5da-9a9f088094c5"
markdown_url: "https://d3tenders.com/contract/ocds-b5fd17-c3c71668-0c85-42e1-b5da-9a9f088094c5.md"
json_url: "https://d3tenders.com/contract/ocds-b5fd17-c3c71668-0c85-42e1-b5da-9a9f088094c5.json"
source: "Contracts Finder"
current_stage: "Award"
buyer: "THE COAL AUTHORITY"
published: "2022-12-29"
---

# Dawdon Short Sea Outfall Repair Works

Buyer: THE COAL AUTHORITY  
Current stage: Award  
OCID: ocds-b5fd17-c3c71668-0c85-42e1-b5da-9a9f088094c5

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## Summary

The Coal Authority is inviting tenders for the "Dawdon Short Sea Outfall Repair Works" project, which involves refurbishing an existing sea outfall structure located in County Durham. The project falls under the industry category of "Underwater pipeline" and has a total contract value of £300,000 GBP. The tender deadline is set for 6th May 2022 with a contract period starting on 1st August 2022 and ending on 31st October 2022. The procurement method is an open procedure, providing opportunities for small and medium-sized enterprises (SMEs) to compete for this works contract.

This tender presents a growth opportunity for businesses specialising in underwater pipeline construction and maintenance. Companies with expertise in subsea pipelines, piping, and general construction work for pipelines would be well-suited to participate. The project requires quality control measures and adherence to design specifications, making it suitable for contractors with experience in similar engineering and construction projects. The location of the project in County Durham provides a regional business growth opportunity for interested contractors.

## Notice

The Coal Authority is looking for a specialist contractor to undertake the refurbishment of existing sea outfall structure at Dawdon Mine Water Treatment Scheme, located approximately 1km south of Dawdon, County Durham. The works will be undertaken in accordance with the NEC4 Engineering and Construction Contract Option B Priced Contract with Bill of Quantities and further details can be found at www.neccontract.com. For further details and full description of the works, please see VI.3 Additional information of this notice for a more detailed description of the works. Here you will find the Scope and instructions on how to register for the event and gain access to the full tender documentation. Additional information: The Dawdon short sea outfall consists of two parallel 200mm pipes with a gravity flow approximately 350m to the discharge point 140m metres from the shore. The pipes were installed through directional drilling and emerge from under the sea bed at the discharge point. Each pipe comes to a T piece with duck bill diffuser elements fitted to each end of the T section. The base of the discharge arrangement was not sufficiently supported and this has allowed the pipework to rotate impacting discharge flows. This needs to be repaired and returned to the correct position with improvements to the support of the diffusers from a pre cast concrete base. The diffusers also had a protective structure that has been dislodged and this needs to be replaced by a new protective sleeve and cap. The protective sleeve can either be a pre-cast concrete pipe or an HDPE pipe section which will be capped by a pre-cast concrete or GRP lid. The replacement duckbills will have to be fitted after the sleeve is placed. Alternatively, arch shaped cut-outs could be implemented, to fit over the duckbills. The "duckbill" check valves will protrude slightly through holes/ windows prepared for purpose and will discharge normally. Construction Due to operational requirements shut down of the pipelines must be well planned and durations kept to a minimum. Based on our feasibility studies the shutdowns are estimated to be no longer than 3 hours per pipeline. All the rehabilitation operations that require no flow through the pipe must be programmed to take place at the same time so that only one shut-down period is required. The following tasks will need to be completed under shutdown: * Disconnection of the flange adapter and replace. * Align the diffuser to vertical and temporarily secure. * Remove the diffuser Tideflex Check Valves. * Drop the protection sleeve into position. * Replacing the diffuser Tideflex Check Valves Divers to conduct the following site preparation activities. * Clearing loose rubble around the flange adapter and concrete base footprint. * Rock drilling may be required to level concrete base footprint. After Pipeline Shutdown * Replace/ rehabilitate and install: * Blank flange o Sacrificial break away spool piece (optional) * Flange Adapter - and right the diffuser to vertical alignment. * Remove the diffuser Tideflex Check Valves. * Place and secure precast concrete base * Drop the protection sleeve into position. * Replace the diffuser Tideflex Check Valves After Resume Pipeline Flow * Grout fill around flange adapter. * Place and secure protective sleeve cap. * A marker buoy with independent anchorage is also to be installed. Evidence of quality control measures and that the installation is as per design are required.

## Key Details

| Field | Value |
| --- | --- |
| Publication source | Contracts Finder |
| Latest notice | https://www.contractsfinder.service.gov.uk/Notice/a1938dd3-52f6-492e-922f-ae849aea5e8c |
| Notice type | Award Notice |
| Procurement type | Standard |
| Procurement category | Works |
| Procurement method | Open |
| Procurement method details | Open procedure (above threshold) |
| Tender suitability | SME |
| Awardee scale | SME |
| All stages | Tender, Award |

## Dates

| Field | Value |
| --- | --- |
| Publication date | 29 Dec 2022 |
| Submission deadline | 6 May 2022 |
| Future notice date | Not specified |
| Award date | 7 Aug 2022 |
| Contract period | 7 Aug 2022 - 31 Aug 2023 |
| Recurrence | Not specified |

## Values

| Field | Value |
| --- | --- |
| Tender value | £300,000 |
| Lots value | Not specified |
| Awards value | £797,315 |
| Contracts value | Not specified |

## Status

| Field | Value |
| --- | --- |
| Tender status | Complete |
| Lots status | Not specified |
| Awards status | Active |
| Contracts status | Not specified |

## Buyer

| Field | Value |
| --- | --- |
| Main buyer | THE COAL AUTHORITY |
| Locality | MANSFIELD |
| Post town | Nottingham |
| Postcode | NG18 4RG |
| Country | England |
| ITL 1 | TLF East Midlands (England) |
| ITL 2 | TLF1 Derbyshire and Nottinghamshire |
| ITL 3 | TLF15 North Nottinghamshire |
| Local authority | Mansfield |
| Electoral ward | Berry Hill |
| Westminster constituency | Mansfield |
| Delivery location | Not specified |

## Supplier

| Field | Value |
| --- | --- |
| Number of suppliers | 1 |
| Supplier names | SOUTHBAY CIVIL ENGINEERING |

## CPV Codes

### Divisions

- 44 - Construction structures and materials; auxiliary products to construction (except electric apparatus)
- 45 - Construction work

### Codes

- 44161400 - Underwater pipeline
- 44161410 - Subsea pipelines
- 44162000 - Piping
- 45231100 - General construction work for pipelines

## Release History

- 29 Dec 2022 at 14:46 - Award - Award Notice - https://www.contractsfinder.service.gov.uk/Notice/a1938dd3-52f6-492e-922f-ae849aea5e8c
- 25 Mar 2022 at 11:04 - Tender - Tender Notice - https://www.contractsfinder.service.gov.uk/Notice/03f254d4-80d3-43ea-83da-8f0e785a2b95

## Documents

- https://www.contractsfinder.service.gov.uk/Notice/a1938dd3-52f6-492e-922f-ae849aea5e8c
  29th December 2022 - Awarded contract notice on Contracts Finder
- https://www.contractsfinder.service.gov.uk/Notice/03f254d4-80d3-43ea-83da-8f0e785a2b95
  25th March 2022 - Opportunity notice on Contracts Finder
- https://www.contractsfinder.service.gov.uk/Notice/Attachment/215a2b80-b418-4d58-a878-66a16f69a3ce
  eTender Registration Information
- https://www.contractsfinder.service.gov.uk/Notice/Attachment/9f268dde-e174-47e7-8ca8-063ec31412c7
  Dawdon SSO Build Contract Scope
- https://inbye.coal.gov.uk/s2c/
  eTender portal link
- https://www.contractsfinder.service.gov.uk/Notice/Attachment/6ab5f95b-4b6a-4e58-9988-64eb45752052
- https://www.contractsfinder.service.gov.uk/Notice/Attachment/0af73f32-6399-4aee-a7d6-a8b447e22c26
  Contract data part one
- https://www.contractsfinder.service.gov.uk/Notice/Attachment/a2933e5a-ad41-4df9-92c0-c1d2b9de9ea8
  Contract data part 2

## Notice URLs

- https://www.gov.uk/government/organisations/the-coal-authority

## Provenance

This Markdown file is an alternate public rendering of the D3 Tenders contract record. The canonical page is https://d3tenders.com/contract/?ocid=ocds-b5fd17-c3c71668-0c85-42e1-b5da-9a9f088094c5. The underlying structured data is available as OCDS JSON at https://d3tenders.com/contract/ocds-b5fd17-c3c71668-0c85-42e1-b5da-9a9f088094c5.json.