A rain barrel is a container positioned to collect and store rainwater runoff from a building’s downspouts. While these systems aid in water conservation and reduce stormwater runoff, they introduce several practical and environmental drawbacks. Understanding these limitations is necessary for responsible rainwater harvesting. This article explores the challenges homeowners may face when incorporating a rain barrel system.
Health and Safety Concerns
Collected rainwater is non-potable and unsafe for drinking, cooking, or bathing without extensive treatment. Rainwater becomes contaminated as it washes over the roof, picking up pathogens like E. coli and Salmonella from bird droppings and organic debris. The water can also accumulate environmental pollutants, including heavy metals like copper, lead, and zinc, which leach from roofing materials and gutters. These contaminants mean the water is unsuitable for irrigating certain edible plants, especially leafy greens, which present a higher health risk if consumed unwashed.
Stored, stagnant water creates a favorable environment for pests, notably mosquitoes, which can breed within four days. To mitigate this, a fine mesh screen must be securely fastened over all openings, including the inlet and overflow pipe. If larvae are present, a biological larvicide containing Bacillus thuringiensis israelensis (BTI) is often recommended, as it is effective against mosquito larvae but harmless to plants.
A full 55-gallon rain barrel contains over 400 pounds of water, creating a significant physical hazard if improperly installed. The immense weight requires the barrel to be placed on a firm, level foundation to prevent tipping, which could cause injury or structural damage. Barrels are often elevated on stands to increase water pressure, making them top-heavy and more prone to falling if placed on uneven ground.
Installation and Space Constraints
The initial setup of a rain barrel requires a financial investment, including the cost of the container, diverters, connecting hardware, and a stand. Finding an appropriate location is a challenge, as the barrel must be positioned next to a downspout and near the area where the water will be used, such as a garden. The available space must be level and structurally able to support the hundreds of pounds of weight when the barrel is full.
Integrating the barrel into the existing gutter system requires cutting the downspout to install a diverter or elbow. This alteration must be precise to ensure proper water flow into the barrel and maintain a path for overflow. The physical presence of a large water tank near the home can also be aesthetically unappealing, and some local homeowner associations or municipalities may restrict the size or placement of collection systems.
The storage capacity of a single rain barrel, typically 50 to 100 gallons, is limited and can be quickly overwhelmed during heavy rainfall. For a roof area of just 1,000 square feet, a one-inch rainfall yields approximately 600 gallons of runoff, meaning most residential barrels will fill rapidly. This limited capacity means the collected water may not be sufficient for prolonged dry periods, yet the barrel still requires a dedicated, visible space year-round.
Ongoing Maintenance Requirements
Rain barrels require consistent attention to prevent problems associated with standing water and debris buildup. Regular cleaning is needed to remove accumulated sediment, algae, and sludge that settles at the bottom, which can clog the spigot and affect water quality. Managing residue requires periodically scrubbing the interior with a non-toxic substance like vinegar or a mild bleach solution, which involves draining and thoroughly rinsing the barrel.
Managing the system’s overflow is a continuous task, as the barrel will inevitably fill, especially after a moderate storm. The excess water must be safely diverted away from the home’s foundation to prevent pooling, erosion, or potential structural damage. If the barrel is not emptied between rain events, it becomes useless for subsequent storms, forcing the homeowner to actively manage the water usage to maintain collection capacity.
Seasonal winterization is necessary in colder climates to prevent the water inside from freezing and expanding, which can crack or permanently damage the barrel. This process involves fully draining the container, disconnecting it from the downspout, and storing it in a protected, dry location for several months. During this time, a temporary downspout extension must be installed to ensure that the roof runoff is directed away from the foundation.