All the Pros and Cons to Harvesting Rainwater

Jess Lynk
Written by Jess Lynk
Updated September 14, 2021
Woman fills up watering can from rain barrel
Leon Harris / Image Source via Getty Images

What you should know before harvesting rainwater

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Having consistent access to water is a must, and an easy way to do so is by harvesting the rain. But before you spring for a system, there are a few things to consider.

What Is Rainwater Harvesting?

Rainwater harvesting is when you capture falling rain in a storage basin, which is then used similarly to well water. This storage basin, aka the “rain barrel,” connects to your gutter through your downspout or a specifically installed pipe. If you plan to drink this water, you will also need to connect a purification system to the barrel. 

Old rainwater tanks looked pretty clunky, but today most rainwater harvesting systems are paired with decorative water features like a waterfall and constructed wetland filters to create a system that circulates water, filters pollutants, and attracts wildlife. Some systems can be completely out of sight (hidden in the ground), but still retain rainwater through pipes to be used when needed.

Pros of Harvesting Rainwater

Harvesting rainwater can help out the environment—and your wallet.

1. Saves You Money

If you are able to harvest enough water for everyday use, you can reduce your water bill. Some common ways you can put harvested rainwater to use are:

  • Flushing your toilet

  • Doing laundry

  • Watering your lawn, garden, and houseplants

  • Cooking

  • Bathing

  • Personal hygiene (washing your face or showering)

2. Easy to Upkeep

Once you pay for the system, it doesn’t cost much to keep it running. It also doesn’t need a ton of maintenance, especially if you’re not drinking the water (and therefore not using a purifying system).

3. Preserves the Environment

Rainbarrel in garden
schulzie - stock.adobe.com

When rainwater is harvested, runoff reduces, which helps protect the environment. According to the Environmental Protection Agency (EPA), nonpoint source (NPS) pollution is the nation’s largest source of water quality problems. NPS pollution is when rainwater flows through surfaces, picking up pollutants and depositing them into our streams, lakes, estuaries, and oceans. When you collect rainwater, you protect other water sources from these pollutants. 

Some of these NPS pollutants include:

  • Motor vehicle contaminants

  • Lawn and garden pesticides and nutrients

  • Road salts

  • Thermal pollution from impervious surfaces such as roofs and roadways

  • Heavy metals from homes and vehicle

4. Gives You an Independent Water Supply

Investing in a water harvesting system can ensure a steady water supply. It can be used as your main water source, or as a supplemental source to turn to as needed.

Cons of Harvesting Rainwater

Although rainwater harvesting has many pros, there are some drawbacks to consider.

1. Unreliable Source

Weather is unpredictable, meaning that rain may not come when you need it. So if you were planning to use rainwater to water your houseplants, but it never rains, this can cause issues (and brown leaves). The good news: If you are able to harvest water during rainy seasons, you can store it for use during drier periods.

2. Expensive Upfront

Although installing a rainwater harvesting system saves you money in the long run, it can be expensive to install. The cost of the system can range anywhere from $120 to $21,000, depending on the type of system. On average, a rainwater harvesting system costs $2,500 to install. And while it might take a while to see a return on your investment, the cost will be recovered.

3. Storage Restrictions

Depending on how big your system is and how quickly you use your water, it may be hard to store your unused supply. Sometimes, depending on rain levels, you may have more water than you can store. Other times, you may not have enough, so tailoring your tank to how much rainwater you would think you need is important upfront.

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