Home / News / Design of overhead rectangular water tank

Design of overhead rectangular water tank

Views: 3     Author: XICHENG EP LTD     Publish Time: 2024-07-05      Origin: XICHENG EP LTD

Designing an overhead rectangular water tank involves several steps, including determining the capacity, selecting materials, and ensuring structural stability. Here's a step-by-step guide to help you through the process:

1. Determine the Capacity

  • Usage estimation: Calculate the daily water requirement and decide on the number of days of storage needed.

  • Formula: Volume (V) = Length (L) × Width (W) × Height (H)

  • Example: For a tank to hold 10,000 liters, V = 10 cubic meters (since 1 cubic meter = 1,000 liters).

2. Select the Dimensions

  • Length, Width, Height: Choose dimensions that fit your available space and desired aesthetic. Ensure the dimensions maintain structural stability.

  • Example: For 10 cubic meters, you could choose L = 2.5m, W = 2m, H = 2m (since 2.5 × 2 × 2 = 10 cubic meters).

3. Material Selection

  • Common materials: Reinforced concrete, steel, or plastic (polyethylene).

  • Considerations: Durability, cost, ease of construction, and maintenance.

4. Structural Design

  • Walls and Base: Must withstand the hydrostatic pressure of the water.

    • Thickness calculation: Depends on material strength and height of the tank.

    • Reinforcement: Typically requires steel bars in reinforced concrete tanks.

  • Roof Design: Should prevent contamination and evaporation, may also need reinforcement.

  • Foundation: Must support the weight of the tank when full. Consider soil bearing capacity.

5. Hydraulic Design

  • Inlet and Outlet: Design for efficient filling and drainage.

  • Overflow pipe: Prevents overflow and directs excess water away safely.

  • Ventilation: Prevents vacuum and allows air movement.

6. Additional Considerations

  • Access: Provide manholes for inspection and maintenance.

  • Ladders and Railings: For safe access.

  • Waterproofing: Especially important for concrete tanks.

  • Insulation: If temperature control is necessary.

design of overhead rectangular water tank

Example Design

Let's design a concrete water tank with a capacity of 10,000 liters.

Capacity: 10 cubic meters (10,000 liters)


  • Length (L): 2.5 meters

  • Width (W): 2 meters

  • Height (H): 2 meters

Material: Reinforced concrete

Wall Thickness:

  • Based on standard practices, a wall thickness of 150 mm (0.15 meters) is often used for small tanks. However, structural analysis is required for precise thickness.


  • Use steel bars (rebar) as per design requirements. For a tank of this size, rebars of 10-12 mm diameter spaced at 150-200 mm are typically used.


  • Ensure the foundation is strong enough to support the tank's weight (concrete slab of adequate thickness, typically around 200 mm, depending on soil conditions).

Hydraulic Design:

  • Inlet pipe: Position at the top of the tank.

  • Outlet pipe: Near the bottom for maximum usage.

  • Overflow pipe: Near the top to handle excess water.

  • Ventilation: Include a vent with a mesh cover to prevent debris entry.

Safety Features:

  • Manhole: For inspection and maintenance, with a secure cover.

  • Ladders and Railings: For safe access to the top of the tank.

PVC (Polyvinyl Chloride)

Structural Analysis

A detailed structural analysis should be performed by a civil or structural engineer to ensure the tank can withstand the loads, including:

  • Water pressure: Varies with depth; highest at the base.

  • Dead load: Weight of the tank itself.

  • Live load: Any additional loads, such as people accessing the top for maintenance.

  • Wind load: If the tank is exposed to strong winds.

  • Seismic load: If located in an earthquake-prone area.

By following these steps and ensuring proper design and construction practices, you can create a durable and efficient overhead rectangular water tank.

 Copyrights 2021 China Xicheng EP Ltd  All rights reserved. 
We use cookies to enable all functionalities for best performance during your visit and to improve our services by giving us some insight into how the website is being used. Continued use of our website without having changed your browser settings confirms your acceptance of these cookies. For details please see our privacy policy.