Whether you’re installing a rainwater harvesting system, borehole pump, filtration system, or full water backup solution, one of the biggest mistakes homeowners and businesses make is ordering equipment before gathering the correct site information.
Water systems are not “one-size-fits-all.” The wrong pump, incorrect pipe size, or undersized storage tank can result in:
- poor water pressure
- system failure
- excessive electricity consumption
- expensive equipment damage
- unnecessary installation costs
That’s why professional installers always begin with a site assessment before recommending pumps, tanks, filtration systems, or irrigation solutions.
In this guide, we explain exactly what information professionals need before ordering equipment or installing a water system.
1. Property Information and Site Details
The first step in planning any water installation is understanding the basic details of the property.
Installers typically need:
Physical Address
This helps determine:
- municipal water regulations
- local groundwater conditions
- rainfall averages
- delivery logistics
ERF or Property Size
The size of the property determines:
- irrigation requirements
- pipe runs
- pump sizing
- storage tank capacity
Large properties require significantly different systems compared to small residential homes.
Roof Surface Area
If you are installing rainwater harvesting, roof size is critical.
Roof area determines how much water can be collected.
Example estimate:
100 m² roof = roughly 60,000 litres per year
(depending on rainfall)
The roof surface area also helps determine:
- tank capacity
- number of downpipes
- filtration requirements
2. Your Water Source
One of the most important factors is where the water will come from.
Different water sources require completely different pumps and filtration systems.
Common sources include:
Municipal Water
Used as a backup supply or pressure system.
Borehole
Requires:
- submersible pump
- pressure controller
- filtration
Wellpoint
Common in coastal areas and the Western Cape.
Rainwater Harvesting
Requires:
- gutter collection
- leaf filters
- storage tanks
- pump system
Greywater Systems
Recycling water from:
- showers
- baths
- washing machines
Each source has different pump and filtration requirements.
3. What Will You Use the Water For?
The purpose of the water system determines the entire system design.
Common uses include:
Irrigation
Garden watering systems require:
- moderate pressure
- high flow rates
Toilet Flushing
Often connected to rainwater tanks.
Car Washing
Requires clean filtered water.
Household Use
May require advanced filtration or purification.
Potable (Drinking) Water
Requires multi-stage filtration and possibly reverse osmosis.
Municipal Backup Connection
Some systems automatically switch between:
- rainwater
- borehole
- municipal supply
Understanding the water demand helps installers choose the correct pump size.
4. Storage Tank Requirements
Water storage tanks are one of the most critical parts of any system.
Installers must determine:
Tank Capacity
Typical residential sizes:
| Tank Size | Use |
|---|---|
| 1000–2500L | small irrigation |
| 5000L | rainwater backup |
| 10,000L+ | full household supply |
Tank Quantity
Sometimes multiple tanks are connected together.
Tank Type
Common options:
- Slimline tanks
- Vertical tanks
- Underground tanks
Tank Colour
Many homeowners prefer tanks that blend into buildings.
5. Pump Requirements
Choosing the correct pump is essential for system performance.
Installers must determine:
Pump Voltage
Most homes use:
- 220V single phase
Larger installations may require:
- 380V three phase
Pump Power (kW)
The power determines:
- water pressure
- flow rate
Too small → weak pressure
Too large → wasted electricity.
Pump Type
Common types include:
| Pump Type | Use |
|---|---|
| Pressure pump | rainwater systems |
| Submersible pump | boreholes |
| Centrifugal pump | irrigation |
| Multistage pump | household pressure |
6. Filtration Requirements
Different water sources require different filtration levels.
Typical filtration systems include:
Sediment Filters
Remove sand, dirt, and debris.
Carbon Filters
Remove:
- chlorine
- bad taste
- chemicals
KDF Filters
Remove heavy metals and bacteria.
Media Filters
Used for larger systems.
Reverse Osmosis
Used when producing drinking water.
The water quality determines which filters are necessary.
7. Pipe Types and Sizes
Incorrect pipe sizing can ruin an otherwise perfect installation.
Installers must determine:
Pipe Material
Common options include:
- HDPE
- LDPE
- uPVC
- SV PVC
- Copper
- Polypropylene
Each material has advantages depending on:
- pressure
- installation location
- budget
Pipe Size
Pipe diameter affects:
- water pressure
- flow rate
- pump performance
8. System Layout and Installation Design
Before installation begins, professionals create a system layout drawing.
This includes:
- tank placement
- pump location
- pipe routes
- filtration placement
- municipal connections
- irrigation zones
Proper layout planning prevents:
- pressure losses
- pump cavitation
- plumbing conflicts
9. Backup Systems
Many water installations include backup systems.
This ensures water is always available.
Common backup options include:
- municipal supply
- borehole
- wellpoint
- secondary storage tanks
Some systems include automatic switching valves.
10. Site Access and Installation Constraints
Installers must also consider practical factors:
Access for Equipment
Large tanks may require:
- crane trucks
- forklift access
Pump Location
Must be:
- protected from weather
- ventilated
- accessible for maintenance
Electrical Supply
Pumps require:
- nearby electrical connection
- appropriate circuit protection
Why a Professional Site Assessment Is Essential
A professional water installer typically completes a site assessment form before quoting equipment or installation work.
This assessment gathers all necessary information including:
- property details
- water source
- intended water use
- tank sizing
- pump requirements
- filtration needs
- piping specifications
- installation layout
Without this information, any quote or system recommendation is just a guess.
Final Thoughts
Ordering pumps, tanks, or filtration equipment without proper planning often leads to:
- incorrect system sizing
- poor water pressure
- unnecessary costs
- repeated installations
A professional site assessment ensures your system is designed correctly the first time, saving both time and money.
If you’re considering installing:
- a rainwater harvesting system
- a borehole pump
- a wellpoint
- a water filtration system
- or a full household water backup solution
make sure the installer collects all the necessary site information before recommending equipment.