1. What is this item?

Collecting rainwater as it falls on farm building rooftops—gutters channel water into storage tanks or underground cisterns. This provides a clean, free water source for irrigation, livestock, or even domestic use, reducing dependence on borewells.

2. How is the Quantity Estimated?

• Calculate catchment area = roof length × width (in m²).

• Rainfall yield ≈ catchment area × annual rainfall (mm) × 0.85 (collection efficiency).

• E.g., a 200 m² roof in a 600 mm rainfall zone ➔ 200×0.6×0.85 = 102 m³ (102 000 L) per year.

3. What are the Cost Components?

• Gutters & Downpipes (PVC/metal)

• First‐flush diverter (to discard initial roof wash)

• Storage tanks/cisterns (plastic, ferrocement, or RCC)

• Pump & piping (if pressurizing water)

• Foundation or plinth for tank support

• Filtration (mesh screen, sand filter)

• Installation labor and plumbing fittings

4. What are the Going Rates & Per Unit Cost?

• Gutters & downpipes: ₹150–₹300 per running meter

• First‐flush device: ₹3,000–₹6,000 each

• Storage tanks:

o 10 000 L plastic tank: ₹25–₹35 per liter capacity → ₹2.5–₹3.5 lakh

o RCC tank (in‐ground): ₹1,200–₹1,600 per cubic meter volume

• Pump & piping: ₹20,000–₹40,000 depending on head and flow

• Installation & plumbing: ₹10,000–₹20,000 per tank

Example: For a 200 m² roof and a 50 000 L tank:

• Gutters (20 m): 20×₹200 = ₹4 000

• First‐flush: ₹4 500

• Tank: 50 000 L×₹30 = ₹15 00 000

• Pump & piping: ₹30 000

• Installation: ₹15 000

Total ≈ ₹16.53 lakh