25 July 2024

Rainwater Harvesting: Unlocking Hidden Cost Savings for Homeowners

Did you know that rainwater harvesting is not only an eco-friendly practice but also a hidden gem for homeowners looking to save money?

In today's world, where sustainability and cost-efficiency are top priorities, rainwater harvesting offers a unique solution that checks all the boxes.

By capturing and storing rainwater, homeowners can reduce their reliance on municipal water supplies, cutting down on utility bills and conserving precious resources.

But the benefits don't stop there.

Rainwater is naturally soft and free from chemicals, making it perfect for various household uses, such as watering plants, washing cars, and even flushing toilets.

With the right system in place, rainwater harvesting can unlock substantial cost savings and provide a sustainable water source for years to come.

The current climate

With New Zealand currently experiencing one of the wettest years on record, harvesting rainwater might seem like a waste of time but that couldn’t be further from the truth.

Whilst our dams and reservoirs here in New Zealand are full to bursting right now, that might not be the case in 12 months' time. In fact, weather forecasters are already predicting a change in the weather patterns over the next 12 months, moving towards an El Nino weather pattern which typically brings hot and dry weather conditions to New Zealand and Australia.

That means there is no better time to maximise your rainwater harvesting than now. With an abundance of rain falling from our skies, get yourself prepared for a long hot and dry summer and become more sustainable when it comes to water usage.

Of course, there are other benefits right now from harvesting the rainwater that falls onto your roof. Our storm drains are struggling to cope with the volume of water that is flowing into them, especially during the torrential downpours we have been experiencing. Collecting some of this rainwater and filtering it into a tank can help to reduce the strain on our storm drains, reducing surface runoff and helping to reduce erosion and other issues caused by too much rainwater runoff.

Looking further afield, other countries are also experiencing unusual weather patterns. The UK is currently in the middle of a heatwave that has seen temperatures already topping out at over 30 degrees which could lead to water restrictions being put into place by the end of the summer.

Certain states in the USA are also experiencing extreme heat conditions, all of which puts a strain on municipal water supplies.

This means that rainwater harvesting is becoming increasingly important no matter where you are in the world.

What is rainwater harvesting?

Rainwater harvesting is the practice of capturing, storing, and utilising rainwater for various purposes. It involves collecting rainwater from rooftops, gutters, and other surfaces, filtering it, and storing it for future use. This ancient technique has been utilised for centuries by civilizations around the world to meet their water needs. However, in recent years, rainwater harvesting has gained renewed attention as a sustainable solution for homeowners.

One of the key components of rainwater harvesting is the collection system. This system typically includes gutters, downspouts, and storage tanks or cisterns. The collected rainwater can then be used for non-potable purposes such as irrigation, washing clothes, cleaning, and flushing toilets. By reducing the demand for municipal water, homeowners can not only save money but also contribute to water conservation efforts.

Rainwater harvesting is particularly beneficial in areas with limited water resources or regions prone to drought. It provides an alternative water source that can supplement or even replace the need for municipal water supply. Additionally, rainwater is naturally soft, making it ideal for certain household tasks where hard water can cause issues.

Benefits of rainwater harvesting

The benefits of rainwater harvesting extend far beyond just cost savings. Let's explore some of the most significant advantages:

1.      Cost savings - One of the most appealing aspects of rainwater harvesting is the potential for significant cost savings. By reducing reliance on municipal water, homeowners can reduce their water bills and save money in the long run. Rainwater is essentially free, and using it for non-potable (and/or potable) purposes can lead to substantial savings over time.

2.      Water conservation - With growing concerns about water scarcity and the environmental impact of water usage, rainwater harvesting offers a sustainable solution. By capturing rainwater, homeowners can reduce the strain on local water supplies, particularly during dry seasons or droughts. This conservation effort contributes to the overall health of the environment and helps preserve water for future generations.

3.      Improved water quality - Rainwater is naturally soft and free from the chemicals commonly found in municipal water sources. This makes it an excellent option for various household uses. For example, plants thrive when watered with rainwater due to its lack of chlorine and other additives. Additionally, rainwater is gentle on clothes, resulting in better laundry results and longer-lasting fabrics.

4.      Reduced stormwater runoff - Stormwater runoff can lead to various environmental issues, including soil erosion and water pollution. By implementing rainwater harvesting systems, homeowners can help mitigate these problems. Collecting rainwater reduces the volume and velocity of stormwater runoff, protecting the soil and preventing pollutants from entering local water bodies.

5.      Sustainable gardening - Rainwater is an excellent source of irrigation for gardens and landscapes. By using rainwater, homeowners can nourish their plants without adding unnecessary chemicals or straining local water resources. This sustainable gardening practice not only benefits the environment but also promotes healthier, more vibrant gardens.

6.      Self-sufficiency - Rainwater harvesting provides homeowners with a sense of self-sufficiency. By having their own water supply, they are less dependent on external sources and are better prepared for emergencies or disruptions in the municipal water system. This self-reliance can bring peace of mind and increased resilience.

How does rainwater harvesting work?

Rainwater harvesting involves a series of steps to capture, store, and utilise rainwater effectively. Let's explore the process in detail:


The first step in rainwater harvesting is the collection of rainwater from rooftops, gutters, or other surfaces. Rainwater is channelled through downspouts and collected in a storage tank or cistern. The collection system should be designed to maximise water capture and prevent debris from entering the storage tank.


Before storing rainwater, it is essential to filter it to remove debris, leaves, and other contaminants. Filtration systems can range from simple mesh screens to more advanced filters that remove smaller particles and sediments. Clean rainwater ensures the longevity of the storage system and prevents clogging or damage to downstream components.


Once filtered, rainwater is stored in tanks or cisterns for later use. The storage capacity depends on factors such as the size of the roof, average rainfall in the area, and intended water usage. Tanks should be made of durable materials that are safe for water storage and designed to prevent contamination.


When the need arises, rainwater can be distributed for various non-potable (and potable) uses. This can be done through gravity flow or by using pumps if necessary. Distribution systems should be designed to supply water efficiently to the desired locations while maintaining optimal pressure and flow rate.

By following these steps, homeowners can effectively implement a rainwater harvesting system that meets their water needs while maximising cost savings and sustainability.

Cost savings through water harvesting

When it comes to cost savings, water harvesting offers numerous opportunities for individuals and businesses alike. By reducing reliance on expensive municipal water supplies, implementing a water harvesting system can result in significant savings over time. Let's explore some of the key ways in which water harvesting can help you cut down on your water bill.

One of the primary areas where water harvesting can lead to cost savings is outdoor water usage. Many homeowners and businesses spend a significant amount of money on watering their gardens, lawns, and landscaping. By collecting rainwater through a harvesting system, you can tap into a free and abundant source of water for irrigation purposes. This eliminates the need to use treated water from the grid, which can be quite costly, especially in areas with high water rates.

In addition to outdoor usage, water harvesting can also help reduce indoor water consumption and, consequently, lower your water bill. By using harvested rainwater for activities such as toilet flushing, laundry, or cleaning, you can further reduce your reliance on municipal water supplies. These everyday activities can account for a significant portion of your water usage, and by switching to rainwater, you can make a noticeable impact on your water bill.

Another cost-saving advantage of water harvesting is the potential for government incentives and rebates. Many governments and local authorities offer financial incentives to encourage the adoption of sustainable practices, including water harvesting. These incentives can take the form of grants, tax credits, or rebates, which can help offset the initial cost of installing a water harvesting system. By taking advantage of these incentives, you can not only save money on your water bill but also reduce the upfront investment required to implement a water harvesting system.

It's important to note that the cost savings through water harvesting are not limited to residential properties. Businesses, especially those that require large amounts of water for their operations, can benefit greatly from implementing a water harvesting system. Whether it's a manufacturing facility, a hotel, or a commercial farm, reducing water consumption can lead to significant cost savings and improve overall operational efficiency. Businesses can also take advantage of government incentives and showcase their commitment to sustainability, which can enhance their brand image and attract environmentally-conscious customers.

The cost savings through water harvesting are substantial and can make a significant impact on your finances. By reducing reliance on expensive municipal water supplies, utilising rainwater for outdoor and indoor usage, and taking advantage of government incentives, individuals and businesses can achieve long-term cost savings while contributing to water conservation efforts. Water harvesting is a win-win solution that benefits both your wallet and the environment.

Tips for maximising cost savings through water harvesting

While water harvesting offers significant cost savings, maximizing its potential requires careful planning and implementation. Here are some tips to help you get the most out of your water harvesting system and achieve optimal cost savings.

·        Calculate your water needs: Before installing a water harvesting system, it's important to assess your water needs accurately. Consider factors such as the size of your property, the number of occupants, and the water-intensive activities you engage in. This will help determine the capacity of your harvesting system and ensure that it meets your water demands.

·        Invest in quality equipment: The effectiveness of your water harvesting system relies heavily on the quality of the equipment used. Invest in high-quality rainwater collection tanks, filters, and pumps to ensure efficient water storage and distribution. Choosing durable and reliable equipment will minimize maintenance costs and maximize the lifespan of your system.

·        Optimise your catchment area: The size and design of your catchment area can significantly impact the amount of rainwater you can collect. Ensure that your rooftops, paved surfaces, or other catchment areas are clean and free from debris that could hinder water flow. Additionally, consider expanding your catchment area to maximize rainfall capture.

·        Implement water-efficient practices: While water harvesting can provide you with a free source of water, it's important to practice water efficiency to further reduce your consumption. Install water-efficient fixtures, such as low-flow toilets and showerheads, and fix any leaks promptly. These small changes can add up to significant water savings over time.

·        Monitor and maintain your system: Regular monitoring and maintenance are essential to ensure the optimal performance of your water harvesting system. Inspect your tanks, filters, and pumps regularly to identify and address any issues promptly. Additionally, clean your catchment area and remove any debris that could clog your system.

·        Educate and promote water conservation: Encourage your family, employees, or community members to adopt water conservation practices. Raise awareness about the benefits of water harvesting and provide tips on how to use water efficiently. By fostering a culture of water conservation, you can further reduce water consumption and maximize the cost savings offered by your harvesting system.

By following these tips, you can maximise the cost savings potential of water harvesting and ensure that your system operates efficiently for years to come. Remember, effective water management is a continuous effort that requires ongoing monitoring, maintenance, and education.


In conclusion, water harvesting is a simple yet effective method that can unlock significant cost savings for individuals and businesses.

By understanding the benefits of water harvesting, implementing the right strategies, and optimising your system, you can achieve substantial cost savings, conserve water, mitigate flooding, and promote self-sufficiency.

Embrace the power of water harvesting and revolutionise your approach to water conservation and cost management.

If you already have a tank installed or you are thinking of installing a tank, a great addition is a water level meter that will enable you to see how much water is in your tank at any time. These are particularly useful for large tanks that are used as the main source of water for a property, however, they can be installed on a wide range of water tanks.

At Smart Water, we have engineered the most advanced tank level indicator available that now offers full cloud connectivity. 
Easy to install yourself, your Smart Water tank indicator provides you with all the information you need from our app or from one of our LCD displays. Find out how much water you consume on average from your tank, accurate pressure data and estimates on when your tank will run out of water based on current usage.

Find out more about our range of products or check out our FAQs for more information.