How Much Does a Rainwater Collection System Cost in 2025?

This article was updated using automation technology and thoroughly reviewed for accuracy by HomeAdvisor Editor Ryan Noonan.

Installing a rainwater collection system costs most homeowners an average of $4,000, with prices ranging from $120 for a simple rain barrel to $21,000 for an extensive harvesting system. Factors like your location, system size, type, materials, and quality greatly influence the overall cost. By hiring a professional, you can ensure you choose the right system and get proper installation to conserve water and reduce your utility bills.

Rainwater Collection System Cost Factors

Along with the basic system type, factors like wet vs. dry systems, permits, guttering, and added extras influence the cost to install your rainwater collection system. Also, remember to consider the ongoing cleaning and maintenance costs.

Dry vs. Wet System

A dry system refers to a rain barrel or roof collection system in which water flows down the pipes and into the storage tanks. The pipes remain empty between rainfalls, hence the term "dry system." These are relatively simple and affordable setups with easy-to-install above-ground storage tanks.

Wet systems are underground systems where the pipes stay full. In these systems, water travels through pipes and collects in the storage tank as more water enters, forcing the excess to spill over into the tank. Wet systems cost more to install due to their more complex setup and excavation requirements.

Rainwater System Component Costs

All types of rainwater systems require the same basic components to function: a conveyance system, a collection method, a filtration system, and storage.

Filtration System

While some water storage systems come with built-in filtration, others require you to add your own filtration system. Find a plumber in your area to learn more about the rates for this project.

Conveyance System

A conveyance system for your rainwater collection costs between $100 and $1,500, depending on the complexity. Downspouts and gutters are a vital part of any rooftop water collection system. Downspouts cost between $300 and $600, while gutters cost $4 to $30 per linear foot, with an average total cost of $1,030 for a pro to install gutters. Your chosen materials and the length of the gutter system impact the total cost.

Water Storage

A simple rain barrel costs $140, while a multi-tank underground system can cost up to $6,000. Water storage container prices vary depending on the amount of water you’ll store and the type of storage.

Collection Area

Average costs for the collection area range from $500 to $9,000, depending on the system type and size. The collection area for a rooftop collection system consists of the gutters and the roof. The collection area for a surface runoff system includes whatever section of ground you designate as where water should flow towards and into your tank.

Above-Ground vs. Below-Ground Storage

Prices on the low end reflect above-ground cisterns that are 50 gallons or less, but most range from 1,000 to 6,000 gallons. Above-ground storage is more affordable than below-ground storage. Above-ground cisterns range from $1,500 to $4,500, though very small ones can cost as little as $120. By comparison, below-ground cisterns start at $5,000.

Above-ground systems are fast and easy to install and adapt to various terrains and locations. This non-invasive installation works with your existing roof, gutters, and downspouts.

In-ground systems require a more complex and invasive installation process. To prevent contamination, the tank must be at least 10 feet from a sealed sewer line and 50 feet from an unsealed line. Therefore, this system isn't necessarily suitable for all properties.

In-ground systems require excavation, increasing overall labor costs depending on the area’s size, soil type, and other factors. Below-ground storage tanks also require higher-quality materials to withstand underground use, which increases the cost.

Cistern Installation

Underground cisterns dramatically increase installation price due to the following component costs:

• Excavating costs: $1,670–$6,720

• Water filtration system costs: $1,130–$3,540

• Cost to regrade a lawn: $1,030–$3,340

• Plumber rates: $45–$200 per hour

• Piping costs and pumps: $200–$500

Rain Barrel Cost

Installing a 100-gallon rain barrel costs $120 to $2,160, depending on the material and labor. Plastic barrels are the most cost-effective but may lack durability. If you plan to connect your rain barrel to an irrigation system, expect to pay more for labor.

Rain Barrel Installation

Hiring a local handyperson costs $70 to $250 for rain barrel installation, not including the barrel. Barrel installation may be as simple as finding the best setup spot or may involve more complex gutter work. Some people even set up sprinkler systems with their rain barrel, likewise adding to installation costs.

Average prices for additional exterior work to accommodate the rain barrel or extra features include:

• Gutter installation costs of $1,170

• Gutter repair costs of $400

• Sprinkler system installation costs of $2,530

Rain Barrel Materials

Rain barrel prices vary by material and size, between $0.50 and $4.00 per gallon. Most homeowners pay $140 for a 40- to 60-gallon barrel.

Maintenance and Cleaning

Maintaining your rainwater harvesting system with filtration costs an average of $740 per year, plus any repairs. A simple rain barrel is the easiest and most cost-effective to maintain; a simple cleaning a few times a year does the job. On the other hand, water filtration systems and underground cisterns come with higher upkeep costs.

Other costs for a rainwater harvesting system over its lifetime include:

• UV bulb and filter replacements: $250 per year

• Gutter cleaning: $170 per cleaning

• Pump replacement: $1,800 every 20 years

Add-Ons and Enhancements

You can keep your rainwater harvesting system simple, particularly if you plan to use it only in the garden. Several rainwater harvesting installations can improve the system by enhancing water cleanliness and efficiency, but they’ll add complexity to your setup.

Water Tank Prices by Material

Water tank prices range from $0.50 to $4 per gallon, but materials can dramatically influence total costs. The water tank’s material offers certain characteristics or advantages.

Concrete

The average price of a 5,000-gallon concrete tank ranges between $3,000 and $6,000. An underground, 5,500-gallon concrete cistern costs between $17,000 and $21,000 to install, including excavation backfilling, grading, and water filtration.

Steel

The average price of a 5,000-gallon steel tank is between $3,000 and $6,000. A small tank, about 80 gallons, costs $300. For a larger tank around 3,750 gallons, expect to pay around $17,000. Steel water tanks range in cost depending on their size and storage capacity. Steel withstands underground use more easily than polyethylene but may be vulnerable to rust and corrosion.

Fiberglass

The average price of a 5,000-gallon fiberglass tank is between $2,000 and $5,000, ranging from $300 to $30,000, depending on storage capacity and size. Fiberglass tanks have versatile applications and are highly resistant to corrosion.

Polyethylene

The average price of a 5,000-gallon polyethylene tank is between $2,000 and $4,000. The cost of polyethylene water storage tanks ranges from $825 to $21,000, depending on the size and water storage capacity of the specific tank. Polyethylene water storage tanks are easy to install, low maintenance, and recyclable. While non-corrosive and durable, they’re not always designed for below-ground use.

Rainwater Collection System Costs by Method

Rooftop rainwater collection and surface runoff harvesting are the two primary methods of collecting rainwater. While both methods collect and store rainwater, their processes vary considerably.

Rooftop

Rooftop rainwater harvesting costs an average of $3,000, ranging between $1,000 and $5,000. This method has more affordable pricing and a simpler setup than surface runoff harvesting. The roof becomes the catchment device, directing the rainwater into the gutters, where it flows into a storage tank for later use.

Surface Runoff

Surface runoff harvesting is significantly more expensive than a roof catchment system, ranging between $8,000 and $17,000 and averaging $11,500. These costs stem from the significantly longer timeline and labor required to excavate the area for the tank before installation.

Surface runoff systems have grates installed beneath the ground, where excess rainwater passes through into pipes and the storage tank. This system helps control erosion from surface runoff and is economical for watering garden plants or topping up a pond in dry weather. To minimize the risk of cross-contamination, the system must be at least 10 feet from a closed sewer line and 50 feet from an unsealed sewer line.

Rainwater Laws

Collecting rainwater isn't illegal, but some areas have restrictions or regulations. States may enforce restrictions during droughts or other water access issues.

Thirteen states allow rainwater collection with some restrictions, 17 states allow it without restrictions, and 20 encourage or incentivize it. Check your local government resources to learn about your state's rainwater laws, regulations, and any potential permit requirements.

Budgeting for a Rainwater Recycling System

Installing a new rainwater recycling system can be a significant investment, but these strategies can help you keep your budget in check:

• Get multiple quotes: Request quotes from multiple contractors to find the best deals or value for your investment.

• Research government incentives: Your project may qualify for government rebates or incentive programs that offset installation costs by up to 50%.

• Bundle services: Ask your contractor if they offer reduced fees for bundled projects like rainwater collection and irrigation systems.

• Simplify: Choose a system that meets your needs without unnecessary features or complexity.

How HomeAdvisor Gets Its Cost Data

No place is more important than your home, which is why HomeAdvisor connects homeowners with local pros to transform their houses into homes they love. To help homeowners prepare for their next project, HomeAdvisor provides readers with accurate cost data and follows strict editorial guidelines. After a project is complete, we survey real customers about the costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.