Cistern Installation for Beginners: Easy Step-by-Step Guide

Quick Summary:
Installing a cistern is straightforward with this beginner’s guide. We’ll walk you through choosing the right spot, gathering your tools, and safely connecting the cistern step-by-step, ensuring a reliable water supply for your garden or home in no time.

Welcome, DIY enthusiasts! Ever felt like setting up a system to store water for your garden or emergency backups was a dark art? For many, the idea of installing a cistern can seem a bit daunting, conjuring images of complex plumbing and tricky connections. If you’ve been putting off that project because you’re not sure where to start, you’re in the right place! This guide is designed specifically for beginners, breaking down the process into easy-to-follow steps. We’ll demystify the jargon, highlight the simple tools you’ll need, and show you exactly how to get your cistern up and running safely and efficiently. Get ready to gain a new DIY skill and secure a convenient water source!

What is a Cistern and Why You Might Need One

Simply put, a cistern is a tank designed to hold water. Think of it as a water reservoir for your home or garden. These tanks can store a significant amount of water, which is incredibly useful for various purposes. For gardeners, a cistern is a goldmine, allowing you to collect rainwater for irrigation, saving money on your water bill and giving your plants the pure, chemical-free water they love. It’s also a fantastic way to be more environmentally friendly by reducing your reliance on treated mains water. Beyond the garden, cisterns can be part of a backup water supply system, providing peace of mind during emergencies or utility outages. They come in many sizes and materials, from small garden-specific units to larger, underground tanks for whole-house supply.

Choosing the Right Cistern

Before you even think about installation, picking the right cistern is key. The best choice for you will depend on what you plan to use it for and how much space you have. Here are a few common types:

Above-Ground Water Tanks: These are the most common for rainwater harvesting in gardens. They are easy to install and come in various shapes and sizes, fitting snugly against walls or standing freely.
Underground Cisterns: These are ideal if space is limited above ground or if you prefer a more discreet look. They require more excavation and careful planning but can hold a large volume of water.
Water Butt (Rain Barrel): A smaller, simpler version of an above-ground cistern, often connected directly to a downspout. Perfect for small gardens and basic watering needs.

When selecting your cistern, consider:

Capacity: How much water do you need to store? For a small garden, a 200-liter water butt might suffice. For larger needs, you might look at 1000-liter or more.
Material: Most are made from durable plastic (like polyethylene) or sometimes wood or metal. Plastic is generally lightweight, UV-resistant, and affordable.
Location: Where will it go? This impacts size, access, and whether it needs to be protected from the elements.
Purpose: Is it just for garden watering, or is it part of a more complex system?

Essential Tools and Materials for Cistern Installation

Gathering your tools before you start is a smart move that saves time and frustration. For a basic above-ground cistern installation, you won’t need a whole workshop. Here’s a checklist of what you’ll likely need:

Tools You’ll Need:

Level: To ensure your cistern is stable and water fills evenly.
Measuring Tape: For accurate placement and cutting.
Drill with appropriate bits: For creating holes for inlet and outlet pipes.
Adjustable Wrench or Pliers: For tightening fittings and connections.
Saw (e.g., hacksaw or PVC pipe cutter): If you need to cut pipes.
Screwdriver set: For any mounting or securing hardware.
Safety Glasses: Always protect your eyes!
Work Gloves: To protect your hands.
Shovel (if preparing a base): For leveling ground.

Materials You’ll Need:

The Cistern: Make sure it comes with or you purchase the necessary inlet and outlet fittings.
Inlet Pipe/Adapter: To connect your water source (e.g., downspout diverter, tap) to the cistern.
Outlet Valve/Tap: To draw water from the cistern.
Overflow Pipe and Fittings: Crucial for managing excess water. Without an overflow, your cistern could overflow from the top, causing a mess.
Plumbing Sealant or PTFE Tape (Teflon Tape): To ensure watertight connections.
Support Base (optional but recommended): A sturdy, level platform like concrete blocks, paving slabs, or a purpose-built stand.
Downspout Diverter (for rainwater harvesting): Connects your roof gutter downspout to the cistern.
Hose or Tubing: For connecting to the outlet tap.

It’s always a good idea to check the manufacturer’s instructions for your specific cistern, as they might recommend particular fittings or tools.

Step-by-Step Guide to Installing Your Cistern

Let’s get hands-on! These steps are for a typical above-ground cistern, often used for rainwater harvesting.

Step 1: Choose the Right Location

This is probably the most important step. Where you place your cistern will affect its functionality and longevity.

Stability: Cisterns are heavy when full! Choose a solid, level surface that can support its weight. A perfectly flat area is crucial to prevent stress on the tank’s structure.
Access: Make sure you can easily reach the inlet, outlet, and overflow points for maintenance and use.
Proximity to Water Source: For rainwater, positioning it near a downspout is ideal. For other uses, consider proximity to your garden taps or mains water connection (if using for topping up).
Drainage: Ensure the area around the cistern can handle overflow without causing waterlogging or damage to your property.
Sunlight: While plastic cisterns are often UV-resistant, prolonged direct sun can degrade materials over time and encourage algae growth inside. Consider a partially shaded spot if possible.

Step 2: Prepare the Base

Even if your ground looks level, it’s best to ensure a perfectly flat and stable base. A wobbly tank is a recipe for disaster.

Clear the area of any debris, rocks, or sharp objects.
If on grass or soil, you might need to dig down slightly and create a firm base using compacted gravel, paving slabs, or concrete blocks.
Use a spirit level on your prepared base to confirm it’s perfectly flat in all directions.

Step 3: Install the Inlet and Outlet Fittings

Most cisterns come with pre-drilled holes or designated areas for fittings. You’ll usually need to fit these yourself (or have them fitted at the factory).

Inlet: This is where water enters. If you’re using a downspout diverter, this fitting will connect to the pipe from your gutter. If filling from a tap, it will be a connection point for a hose or pipe.
Outlet: This is where water exits, usually fitted with a tap or valve. It’s often located a little way up from the bottom to avoid drawing sediment, but low enough to allow most of the water to drain.
Overflow: This is vital! It’s typically a larger pipe near the top of the cistern. When the cistern is full, excess water will drain out through this pipe, directing it away from the cistern to a safe drainage point (like a soakaway or storm drain).

When fitting these, remember to:

Use the provided seals and washers.
Apply PTFE tape or plumbing sealant to threaded connections to ensure a watertight seal.
Tighten fittings firmly but avoid overtightening, which can crack plastic.

For rainwater harvesting, a downspout diverter is a common inlet solution. These clever devices collect water from your gutter and channel it into the cistern, often with a mechanism to stop filling when the cistern is full and allow normal gutter flow otherwise. Many are available with built-in filters to remove leaf debris. You can find excellent installation guides and product information from organizations like The U.S. Environmental Protection Agency (EPA), which offers insights into water conservation practices.

Step 4: Connect the Water Source (Inlet)

How you connect your water source depends on your setup.

Rainwater Harvesting: If using a downspout diverter, cut a section out of your existing downspout at the appropriate height (follow the diverter’s instructions). Fit the diverter and connect the connecting pipe to your cistern’s inlet. Ensure the connection is secure and angled downwards towards the cistern.
Mains Water Supply (for topping up): Connect a hose or pipe from your outdoor tap to the cistern’s inlet fitting. You might want to consider a float valve on the inlet that automatically shuts off the water supply when the cistern is full, preventing overflow and wastage. You can find more about plumbing components at resources like The Engineering Toolbox, which details various pipe fittings and their uses.

Step 5: Connect the Outlet and Overflow

This is where you’ll get water out and manage excess water.

Outlet: Screw your chosen tap or valve into the outlet fitting. If it’s a threaded connection, use PTFE tape or sealant. If it’s a push-fit or compression fitting, follow the manufacturer’s instructions. You can then attach your garden hose or a pump to this tap.
Overflow: Connect a pipe (usually the same diameter as the fitting) to the overflow outlet. This pipe should be angled to allow gravity to carry water away to a safe location. Ensure this is a continuous downward slope to prevent blockages. Avoid connecting it directly to the drain unless local regulations permit, as it can sometimes cause issues with foul air and blockage. A soakaway or simply diverting it to a lower part of the garden is often best.

Step 6: Position and Secure the Cistern

With all fittings in place, it’s time to put the cistern onto its prepared base.

Carefully lower the cistern onto the prepared base.
If your cistern has base flanges or mounting points, now is the time to secure it to the base if required. For very large tanks, or in areas prone to high winds, some form of anchoring might be necessary. Check the manufacturer’s recommendations.
Use your level again to double-check that the cistern is sitting perfectly upright.

Step 7: Test for Leaks

Don’t wait until it’s full to find a leak! Start slowly.

If you’ve connected to a water source, let a small amount of water in.
Carefully inspect all the fittings you installed (inlet, outlet, overflow) for any drips or leaks.
Check around the tank itself for any defects.
If you find a leak at a fitting, turn off the water, drain the tank slightly if necessary, and re-seal the connection.
Once you’re confident there are no leaks, you can begin to fill the cistern fully.

Step 8: Filling and First Use

If you’re using it for rainwater, wait for the rain! If you’re filling from a tap, do so gradually.

Monitor the cistern as it fills.
Check the overflow pipe is working correctly when the cistern reaches its maximum capacity.
Once full, open the outlet tap and let some water out to ensure it flows freely.

Congratulations! You’ve successfully installed your first cistern.

Maintaining Your Cistern for Longevity

A little regular maintenance goes a long way in keeping your cistern in great shape and ensuring the water quality is good.

Regular Checks:

Inlet Filter: Clean out any leaves or debris from your downspout diverter or inlet filter regularly, especially after windy or rainy periods.
Overflow: Ensure the overflow pipe is clear and not blocked by leaves or debris.
Tap/Valve: Check that the outlet tap is functioning correctly and not leaking.

Cleaning:

Over time, sediment can build up at the bottom, and algae might start to grow, especially if it’s exposed to sunlight. How often you clean depends on usage and conditions, but an annual clean is a good starting point.

Drain the cistern as much as possible.
You can use a stiff brush to scrub the inside walls. A mild, environmentally friendly cleaner or just water and a brush usually suffice. Avoid harsh chemicals.
Rinse thoroughly.
For deeper cleaning of stubborn algae, some recommend a dilute solution of water and vinegar, followed by a very thorough rinse.

Winterizing (if applicable):

In regions with freezing temperatures, you’ll need to prepare your cistern for winter.

Drain the cistern completely to prevent water from freezing and expanding, which could crack the tank or fittings.
Disconnect any pipes that could hold water and freeze, or ensure they are drained.
Some people cover their cisterns with insulating material.

Pros and Cons of Cisterns

Like any home improvement project, installing a cistern has its advantages and disadvantages. Understanding these can help you make an informed decision.

Pros	Cons
Water Conservation: Excellent for rainwater harvesting, reducing reliance on mains water.	Initial Cost: The cistern and any associated plumbing can be an upfront investment.
Reduced Water Bills: Using free rainwater significantly cuts down your water expenses.	Space Requirement: Cisterns take up space, and larger ones can be quite bulky.
Improved Plant Health: Rainwater is free of chlorine and other chemicals found in tap water, which is better for plants and gardens.	Maintenance: Requires regular checks and occasional cleaning to keep it functioning well and prevent issues.
Emergency Preparedness: Provides a water reserve during power outages or other utility disruptions.	Potential for Stagnation: Water left standing for too long can become stagnant and may require treatment before use for non-garden purposes.
Environmental Benefit: Reduces strain on municipal water supplies and helps manage stormwater runoff.	Aesthetics: Above-ground cisterns might not be the most attractive feature in your garden, though many designs are now quite sleek.
Independence: Less reliance on external water suppliers for certain needs.	Freezing: In colder climates, they need to be winterized to prevent damage from ice.

Frequently Asked Questions About Cistern Installation

Q1: How much does it cost to install a cistern?

The cost varies widely. A simple 200-liter water butt might cost from £50-£150 ($60-$180 USD). Larger tanks, underground systems, or those with advanced filtration and pumping systems can cost hundreds or even thousands of dollars.

Q2: Do I need planning permission to install a cistern?

For typical above-ground water butts and garden cisterns, planning permission is usually not required. However, for large underground systems, or if you are in a conservation area or your property is listed, it’s always best to check with your local council. For rainwater harvesting, some regions might have specific regulations regarding the use and discharge of rainwater.

Q3: Can I connect a cistern directly to my mains water supply?

Yes, but it’s strongly recommended to use a backflow prevention device or a float valve. This ensures that if the mains pressure drops, water cannot be siphoned from your cistern back into the mains supply, which could contaminate it. A float valve will also automate filling and prevent overflow. It’s crucial to comply with local plumbing regulations.

Q4: How often should I clean my cistern?

For garden use, cleaning once a year is generally sufficient. If the water is intended for non-potable domestic use (like flushing toilets) using a pumped system, more frequent checks and cleaning may be advisable, perhaps every 6-12

Installation of Cistern for Beginners: Genius Guide