How to Install Rainwater Harvesting System – Rainwater Harvesting System

The following steps shows how to install a rainwater harvesting system for rainwater attenuation.

We will need the following components: Rainwater Interception Bask device, first flush device, automatic filter, rainwater modular tank, geomembrane, geotextile, Pipe connection box for inlet/outlet pipe, pipe for water backwash, pipe for overflow, etc.

Step 1. Prepare the foundation for rainwater harvesting system.

Based on the size of the rainwater pool, excavate a foundation pit with each edge at least [300mm ~ 500mm] longer than the rainwater pool. It is important that there should be enough room at all sides of a rainwater pool, so it can be back filled and compacted with sand. The sidewall slope should be strictly in accordance with relevant standards so that the entire pool is trapezoidal shaped, which can reduce any potential lateral pressure onto the rainwater matrix and prevent settlement of the foundation edges and landslides. Set up safety fences and safety warning lines around the excavated pit.

A concrete cushion is needed for the following situation: 1.there’s groundwater seepage,2.there’s silt layer, 3.there’s frozen soil backfilling, 4. near basement and underground buildings, 5. pipeline tunnel crossing at the bottom, 6. parking lot at the top, 7. traffic road at the top, 8. buildings at the top and other conditions. Grading strength of concrete cushion depend on the actual situation.

Pool foundation layer (if necessary): compacted and leveled with excavated soil or fine river sand (compact density ≥ 95%)【≥ 100mm】 (If the foundation soil is soft , build a solid foundation and then put on a layer of fine sand) Reinforced concrete foundation【c25】 thickness 【≥200mm】 or Plain Concrete foundation 【c15】 thickness【≥100mm】

Put a layer of 100mm fine sand and level the foundation (compact density ≥ 95%), so the product can be installed flatly and the drainage at the pool bottom could be more effective in case of heavy rains or storms.

The rainwater matrix must be installed on a solid foundation to ensure its structural integrity, and both longitudinal and horizontal excavation must be made vertical.