Interest in rainwater harvesting has surged recently for two main reasons: its high-quality water and the growing desire to reduce reliance on treated water. Rainwater is naturally soft and pure, with a slight acidity, free from disinfectant by-products, salts, minerals, and other contaminants. Additionally, with aquifers being depleted, rainwater harvesting is increasingly valued as a sustainable conservation method to help alleviate pressure on conventional water sources.

An efficient rainwater harvesting system can capture approximately 0.62 gallons of water per square foot of roof area for each inch of rainfall. However, in practice, some water loss occurs due to factors like first flush, evaporation, splash-out, gutter overshoot, and potential leaks. We recommend assuming an efficiency of about 75 to 85 percent for the system. For your home in Spring Branch, using a collection rate of 0.62, a system efficiency of 0.85, and an average annual rainfall of 32 inches, you can expect to collect around 34,000 gallons of rainwater each year (0.62 x 0.85 x 2,000 x 32 = 33,700 gallons annually).

A 'dry' system plumbing configuration directs rainwater from your roof straight to your storage tank without any underground piping. It’s called a 'dry' system because the conveyance pipes drain and dry out when it’s not raining. These systems are straightforward, as water flows directly into the tank by gravity. To function correctly, all conveyance pipes must be positioned above the tank inlet and slope toward the storage tank. Typically, dry systems have short conveyance pipe runs and involve only one or two downspouts. In contrast, a 'wet' system configuration is more complex but often offers greater security. This setup channels rainwater from the roof underground through pipes and into your rainwater harvesting tank. In a wet system, rainwater flows through airtight PVC downspouts into sealed underground pipes, which then direct the water back up to the tank via a riser pipe positioned near the top of the tank. To ensure proper function, there needs to be a sufficient drop (approximately 2 feet) from the bottom of the gutter to the top of the tank, allowing gravity to fill the tank. These systems are termed "wet" because water remains in the pipes even after rainfall.

A complete rainwater harvesting system for a typical single-family home usually ranges from $30,000 to $50,000. The largest expense in such a system is typically the storage tank, with costs varying based on size and construction material. On a per-gallon basis, plastic tanks may cost around $0.50, while steel tanks can exceed $4. In addition to the tank, other components like gutters, downspouts, roof washers, pumps, and pressure tanks will contribute to the overall cost. Choosing professional installation can further increase expenses. If the system is intended for drinking water, additional costs for disinfection will need to be factored in. We can assist you in designing a cost-effective system tailored to your needs.

The notion that there is an overabundance of water available in the Texas Hill Country is misleading. With Comal County's population projected to double in the next 50 years, our existing surface water and groundwater resources are being increasingly depleted, as monitored by the Comal Trinity Groundwater Conservation District. Some areas within the county and neighboring counties are already experiencing shortages due to demand surpassing available supplies. In this context, rainwater harvesting presents a valuable opportunity to conserve and extend our existing water resources.

Collected rainwater is safe to drink after proper filtering and UV treatment. As rain falls through the atmosphere and onto the catchment surface, it may pick up microbial and chemical contaminants, as well as particulate matter.

Cost-effective: The water is essentially free, with costs limited to collection and treatment.

Proximity: The end use is close to the source, minimizing the need for expensive distribution systems.

Alternative supply: Rainwater serves as a reliable source when traditional options like groundwater are unavailable or of poor quality.

Appliance longevity: The zero hardness of rainwater helps prevent scale buildup in appliances, extending their lifespan.

Sodium-free: Rainwater is naturally free of sodium.

Ideal for landscaping: Rainwater is excellent for landscaping, promoting healthy plant growth.

Stormwater management: Harvesting rainwater reduces flow into storm sewers, mitigating the risk of downstream flooding.

Peak demand relief: It helps utilities manage peak water demands during the summer months.

Lower utility bills: By harvesting rainwater, homeowners can decrease their utility expenses.

A UV water purifier uses germicidal ultraviolet wavelengths to expose living organisms, such as bacteria, viruses, and cysts (including Cryptosporidium and Giardia). The UV light disrupts the DNA of pathogenic microorganisms, preventing them from reproducing. As water flows through the ultraviolet light filter, the bacteria are neutralized, rendering the water safe to drink.