From drinking, cooking, cleaning, and bathing – we all use water every day.  Rainwater harvesting systems are a great way to harvest that water we so desperately need.  There are so many reasons to get a rainwater harvesting system, but a few reasons not to as well.

Harvesting rainwater has the advantage of putting you in control of your own water supply.  Plants grow better with rainwater. Rainwater Harvesting also costs money, takes up space and can breed pathogens and harmful insects, which can be a real disadvantage.

So is it worth installing a rainwater harvesting system at your home?  Or do the disadvantages outweigh the advantages?  Read on to learn about each one, then you can decide whatʻs best for you.

Advantages Of A Rainwater Harvesting System

You are in control of your water

Rainwater harvesting puts you entirely in control of the water supply on your homestead. This means you aren’t dependent on a public water system and you get to determine what chemicals or treatment is used to clean your potable water – for example, you can avoid fluoride.

In the long-run, you save a significant amount of money by harvesting rainwater. However, don’t assume that it will be entirely cost-free in the beginning (scroll down for the disadvantage of the initial investment of a rainwater harvesting system).

I feel comforted seeing my water tank in my backyard full of water.  I know that I have water when I need it.  

Plants grow better with rainwater

It makes perfect sense that rain helps plants grow, but it’s more than just being ‘water’. Water from public utilities has been chlorinated, which has a negative effect on plants. 

Rainwater, however, is purer.  In fact, rainwater has many minerals that the public water supply lacks. Once you start saving rainwater and using it in your garden, you are sure to notice that your plants grow healthier.

Reduces soil erosion

The rain is going to fall whether you save it or not. But, if there is an exceptionally heavy storm, rainwater can actually be a nuisance. Too much rain combined with poor drainage around your property can result in flooding or soil erosion.

Instead, we can construct water harvesting swales, ponds or terraces to slow, spread and sink the rainwater.  In the process we minimize soil loss and rehydrate our aquifers.

Not all rainwater harvesting has to take place in a water tank.

Drought Resilience

Another factor that some people neglect to consider when harvesting rainwater, is that it makes you independent of the weather, in regards to rain. 

Water collected in rainy times to be used during dry times increases your drought resiliency.  Allowing the soil to act as a sponge during rain events can increase the water levels in your soil by 6xʻs or more, making healthy strong plants!

Properly sized tanks filled with water provide the daily needs of a household, even during dry periods.

While your neighbors may be running with limited water, or even dealing with water shortages for their gardens, your water comes from your own personal reservoir.

Recharge Groundwater

As I mentioned early, constructing water harvesting earthworks such as on contour swales, ponds and terracing can increase the water holding capacity of almost any landscape as well as aid in the recharge of groundwater resources.

I once built some swales in southern California, which gets about 14” of rain per year.  After a series of storms that filled the swales up, springs were beginning to appear that would bubble up from the ground weeks after the last rain storm.  It was a sight to see.

Rainwater harvesting can have a real positive impact on so many things, thereʻs almost no reason why anyone should go without, except for maybe these next 5 reasons.

Related: 12 Ways To Use Harvested Rainwater

Disadvantages Of Rainwater Harvesting

Rainwater Harvesting Can Have Some High Startup Costs

Honestly, setting up your home to harvest rainwater in a responsible way is not cheap. The initial costs are quite an investment, so don’t expect to come out even when harvesting rainwater immediately, it will take some time before you see the financial benefits.

There is also a very wide margin of costs, depending on what type of rainwater harvesting system you are going to implement. Underground tanks? Pumps? I’ve written an entire post about the costs of rainwater harvesting, check it out here.

Water Tanks Take Up Space

If you’re storing rainwater, then you must store it somewhere. Some people don’t like big water tanks in their backyard, but there isn’t much you can do about that, unless you decide to make underground tanks.

While underground tanks won’t be an eyesore, you will have to put in more work and finances to set up these water harvesting systems. Consider if you’re okay with visible tanks around your property for years to come, or want to pay more to have your tanks underground, instead.

Pathogens and bugs

Being ‘pure rainwater’ sounds lovely, but it doesn’t always stay pure. Public water is treated with chemicals for a reason: to kill pathogens and bugs. In order to keep your water safe and potable for consumption, you will need to take precautions and treat your water to prevent illness.

Some of the nasty microbes you need to protect yourself from include salmonella and giardia. 

Now, you don’t have to use all the chemicals that the government uses to clean your consumable water. But, you should use something to disinfect and treat your water, especially if you want to make it potable. Three common solutions for treating your water are:

  • Chlorine – I put about a cup per 2000 gallons every month or so.
  • UV Lights (Specifically designed for water treatment)  This system kills off pathogensby subjecting them to a UV light.
  • Activated charcoal


In most cases of rainwater harvesting, you’ll be directing water off your roof into gutters and downspouts. To insure the integrity of your rainwater, you will need to keep all of these areas spic-and-span. 

Do not allow leaves or debris to collect around your roof or gutters – you may need to regularly trim trees around your home as a preventative measure.

You will also need to put in the work to ensure your tanks are properly maintained and that algae doesn’t begin growing in your stored rainwater. This may seem minor at first, but if you neglect proper maintenance, it will be time-consuming and costly to repair your water system.

Other types of maintenance include cleaning your filters, cleaning out sediment that builds up in your tanks and looking closely for any leakages in the system.

You are in control of your water

Ahh, here’s a catch; both an advantage and disadvantage of rainwater harvesting, being in control of your own water supply.

There may be no water bill.  No one is poisoning your water.  But you do have to manage it.  You have to keep it clean.  You have to get out there in the middle of the night and fix the broken pipe.  You.  

That can be too much responsibility for some people, but in reality, itʻs not that hard once you create a system.

When you consider rainwater harvesting in the long-term, there are certainly some disadvantages and up-front costs. But I believe that the initial investment is worth it to be in charge of your own water and have an independent, off-grid homestead.

But ultimately, the choice is yours.

Further Reading