Annual Maintenance Contract ( 01/01/2027- 12/31/2029)

Waste Water Tank Cleaning & External Sewage Drain Line High-Pressure Water Jetting

1. General

The Contractor shall provide a comprehensive Annual Maintenance Contract (AMC) for the inspection, cleaning, flushing, disinfection, maintenance, and preventive servicing of all designated wastewater tanks and associated external sewage drainage pipelines. The Contractor shall provide all labour, supervision, transportation, tools, equipment, consumables, chemicals, high-pressure water jetting equipment, vacuum tankers, pumps, safety equipment, testing instruments, permits (where applicable), sludge removal, waste disposal, reporting, and any other resources necessary to complete the works.

All works shall be executed in accordance with UAE Municipality regulations, local environmental requirements, Occupational Health & Safety (OHS) regulations, confined space entry procedures, and recognized industry best practices.

The objective of this AMC is to maintain the wastewater collection system in a clean, hygienic, and fully operational condition, preventing sludge accumulation, blockages, foul odours, flooding, equipment failure, and environmental contamination.

2. Asset Details

2.1 Wastewater Tanks

Tank No.	Type	Dimensions	Capacity
01	RCC Wastewater Tank	3.0m × 3.0m × 2.0m	18 m³
02	RCC Wastewater Tank	3.0m × 3.0m × 2.0m	18 m³
03	RCC Wastewater Tank	3.0m × 3.0m × 2.0m	18 m³

Total Tanks: Three (3)

Each tank is equipped with:

• Access hatch
• Installed wastewater pump
• Inlet and outlet pipework

 

 

 

 

2.2 External Drainage System

The drainage system consists of:

• External suspended sewage pipeline
• Basement installation
• Hanging pipe support system
• Pipe diameters:
  • 4 inch
  • 6 inch
• Approximate total pipeline length: 400 Linear Metres

3. Wastewater Tank Cleaning

The Contractor shall clean every wastewater tank during each scheduled quarterly visit.

3.1 Preparation

Before commencing work, the Contractor shall:

• Coordinate work schedule with the Client.
• Obtain all required permits.
• Conduct Job Safety Analysis (JSA).
• Prepare Risk Assessment (RA).
• Isolate electrical supply to pumps where necessary.
• Install barricades and warning signage.
• Verify confined space requirements.
• Ensure all personnel are trained and certified for confined space work where applicable.
• Conduct gas testing before entry.

3.2 Dewatering

The Contractor shall:

• Pump out all wastewaters.
• Utilize submersible pumps and/or vacuum tanker.
• Prevent overflow during pumping.
• Protect surrounding areas from contamination.
• Ensure wastewater is transported safely

3.3 Sludge Removal

Completely remove:

• Sludge
• Mud
• Sand
• Silt
• Grease
• Oil residue
• Organic deposits
• Floating debris
• Plastic waste
• Foreign objects
• Sediment

Removal shall be carried out using:

• Vacuum suction
• Manual removal
• Shovels
• Buckets
• Sludge pumps
• Industrial cleaning equipment

3.4 Tank Cleaning

Following sludge removal:

The Contractor shall thoroughly clean:

• Tank floor
• Tank walls
• Corners
• Access ladder
• Pipe penetrations
• Pump base
• Pump guide rails
• Internal surfaces

Cleaning shall include:

• High-pressure water washing
• Manual scrubbing
• Removal of biofilm
• Removal of hardened deposits
• Complete flushing

No visible sludge shall remain after cleaning.

 

3.5 Disinfection

Upon completion:

Apply Municipality-approved:

• Disinfectant
• Deodorizer
• Odour neutralizer

Products shall be:

• Non-toxic
• Non-corrosive
• Environmentally friendly
• Safe for RCC structures

3.6 Inspection

Inspect and report the condition of:

Civil

• Concrete walls
• Floor
• Roof slab
• Cracks
• Water seepage
• Structural deterioration

Mechanical

• Pumps
• Guide rails
• Float switches
• Isolation valves
• Check valves
• Discharge piping
• Supports
• Couplings

General

• Access cover
• Locking arrangements
• Ventilation
• Cleanliness
• Odours

3.7 Functional Testing

Where pumps are installed:

Verify:

• Automatic operation
• Manual operation
• Float switch functionality
• Pump discharge
• Vibration
• Noise
• Leakage
• Alarm operation (where applicable)

3.8 Waste Disposal

The Contractor shall:

• Remove all sludges.
• Remove wastewater.
• Transport waste using licensed vehicles.
• Dispose of waste at Municipality-approved disposal facilities.
• Provide disposal records upon request.

No waste shall remain on site.

4. External Sewage Drain Line High-Pressure Water Jetting

The Contractor shall carry out complete preventive jetting of the external sewage drainage network.

4.1 Pre-cleaning Inspection

Inspect:

• Manholes
• Inspection chambers
• Hanging supports
• Pipe joints
• Access points
• Pipe alignment
• Leakage
• Visible defects

Identify:

• Grease accumulation
• Sediment
• Partial blockage
• Root intrusion
• Damaged supports
• Pipe deformation

4.2 High-Pressure Water Jetting

Provide commercial-grade High-Pressure Water Jetting (HPWJ).

Suitable operating pressure shall be selected according to pipe material and diameter.

Clean the entire accessible pipeline.

Remove:

• Grease
• Soap deposits
• Sludge
• Mud
• Sand
• Silt
• Food waste
• Organic matter
• Sediment
• Minor tree roots
• Minor blockages
• Foreign objects

Flush until clean water flows freely.

4.3 Cleaning of Manholes & Chambers

Open accessible manholes.

Remove:

• Debris
• Sediment
• Sludge

Clean:

• Benching
• Channels
• Covers
• Frames

Securely reinstate all covers after completion.

4.4 Final Flow Test

Following jetting:

Verify:

• Free flow
• No standing water
• No remaining obstruction
• Proper discharge

4.5 Reporting

Record:

• Cleaning completed
• Approximate blockage locations
• Pipe defects
• Leaks
• Damaged supports
• Areas requiring repair

Include photographs.

5. Equipment

The Contractor shall provide, as a minimum:

• High-pressure water jetting machine
• Vacuum tanker
• Sludge suction machine
• Submersible pumps
• Portable generator
• Flexible jetting hoses
• Jetting nozzles
• Drain rods
• Pressure washer
• Gas detector
• Tripod and rescue equipment for confined space entry
• Ventilation blower
• Portable lighting
• PPE
• Barricades
• Warning signs
• Spill containment kits
• Cleaning tools

All equipment shall be calibrated, maintained, and suitable for the intended application.

6. Health, Safety & Environmental Requirements

The Contractor shall:

• Comply with all UAE HSE legislation.
• Conduct Risk Assessment and Job Safety Analysis before each visit.
• Implement confined space entry procedures.
• Test atmosphere before tank entry.
• Provide standby personnel during confined space operations.
• Use full Personal Protective Equipment (PPE).
• Secure work areas.
• Prevent spills and environmental contamination.
• Maintain good housekeeping.
• Restore the site to its original condition upon completion.

7. Service Frequency

The following preventive maintenance services shall be carried out as per below,

Service	Frequency
Waste Water Tank Cleaning – Sumpit	4 Times Per Year (Quarterly)
External Sewage Drain Line High-Pressure Water Jetting	2 Times Per Year (Semi Annually)

Emergency callouts for blockages, subject to the terms of the AMC, shall be attended within the agreed response time.

8. Deliverables

After each scheduled visit, the Contractor shall submit:

• Service Completion Report
• Preventive Maintenance Checklist
• Before and After Photographs
• Inspection Findings
• Defect Report
• Recommendations for Corrective Works
• Waste Disposal Records
• Pump Functional Test Results
• Attendance Records Signed by the Client Representative

9. Performance Standards

The Contractor shall ensure that:

• Wastewater tanks remain clean, hygienic, free of sludge, and free from foul odours.
• Pumps and associated equipment remain operational following each service.
• External sewage drain lines are clean, free-flowing, and capable of conveying wastewater without restriction.
• No damage is caused to tanks, pumps, pipelines, or associated infrastructure during the execution of the works.
• All sludge, wastewater, and debris are removed from the site and disposed of at approved facilities.
• Services are completed with minimal disruption to the Client's operations and in full compliance with applicable UAE Municipality, environmental, and health and safety regulations.