DCWW2115 Service Reservoir Cleaning, Maintenance and Refurbishment CoP

Overview And Objectives

DCC intends to award a Framework Agreement for Service Reservoir Cleaning, Maintenance and Refurbishment services. It is a business-critical service required to:

• maintain the cleanliness, integrity and operational condition of DCC’s potable water storage assets;
• support the safe and timely return of service reservoirs to operation following planned cleaning, inspection and minor remedial works; and
• support compliance with Drinking Water Inspectorate (DWI) requirements, DCC’s internal standards and applicable water quality legislation.

The Framework will be used to provide cleaning and maintenance for potable water tanks across DCC’s operational area. There are approximately 828 tanks within DCC’s estate that require routine cleaning and inspection in accordance with PNL 810 (DCC’s internal standard for drain downs and cleaning of service reservoirs) to meet Drinking Water Inspectorate (DWI) regulations.

Tanks include below ground and above ground steel or concrete tanks as well as a small number of water towers however most tanks are square, underground concrete structures.

Ensuring a clean and consistent water supply is core to DCC services and is linked directly to corporate key performance indicators.

The proposed contract term is 3 years, with the option to extend for a further 5 years (2 + 2 + 1 years). The estimated value of the framework for the initial three-year term is £25.5 million based on estimated annual expenditure of approximately £8.5 million. The value across the maximum term of 8 years is £68m.

Scope

The scope includes the following elements:

Cleaning

This includes the cleaning and disinfecting of the tanks normally with the use of high-pressure water or soft brush as appropriate and DWI Approved disinfectant. In some instances, it may be a requirement to carry out chemical cleaning with the use of a DWI approved chemical.

The tasks to be carried out will include:

• Cleaning and disinfection of potable water storage tanks using appropriate methods and DWI-approved products
• Inspection of service reservoirs as part of cleaning activities

Maintenance

Maintenance activities are usually identified at the time of cleaning by the Supplier and instructed by DCC to enable the tanks to be safely returned to service. These tend to be internal and external works for concrete repairs and coatings, internal and external steel repairs, membrane fitting and repairs, replacement of ladders and pipework, joint repairs, external earthworks repairs and joint repairs. Emergency reactive repairs to concrete/ pipework / liner etc. may also be required on occasion. These works will exclude any work that involves significant engineering difficulties such as:

• Any structural modifications to the tank(s);
• Any works on the embankments surrounding the tank(s);
• Any modifications to the pipework that can influence the hydraulic performance of the tank(s);
• Any works that alters the operating capacity of the tanks;
• Any works that constitutes the appointment of a Panel Engineer under the Reservoirs Act.

The tasks to be carried out will include:

• Minor planned and reactive remedial works, including concrete and steel repairs, coatings, membranes, ladders, pipework, joints and external earthworks.
• Emergency reactive repairs where required.
• Activities necessary to support the safe return of reservoirs to service.

The Framework Agreement will be procured as a single Lot, with two Suppliers appointed to the Framework.