Our Water Supply vs. The I35 Corridor Growth

by, Holly Ratcliff

The water cycle is often perceived in general terms: precipitation, evaporation, transpiration, and condensation. Yet, a series of policies and procedures also facilitate the process, increasing its pace to provide a larger number of citizens with water. As San Marcos’ number of residents rises, several organizations are essential in the regulation and protection of its natural resources.

On December 2, 1970, the U.S. Environmental Protection Agency (EPA) was “born in the wake of elevated concern about environmental pollution… to consolidate in one agency a variety of federal research, monitoring, standard-setting and enforcement activities to ensure environmental protection.”

Soon after, Texas Legislature followed in suit and created the Texas Natural Resource Conservation Commission, later renamed the Texas Commission on Environmental Quality (TCEQ). The TCEQ “strives to protect our state’s public health and natural resources consistent with sustainable economic development. [Their] goal is clean air, clean water, and the safe management of waste.”

Although it is important to preserve water, for drinking or otherwise, the amount of water on Earth is fixed: “Through the natural water cycle, the earth has recycled and reused water for millions of years” (EPA).

Water is naturally recycled through “unplanned” processes: “A common example of unplanned water recycling occurs when cities draw their water supplies from rivers, such as the Colorado River and the Mississippi River, that receive wastewater discharges upstream from those cities. Water from these rivers has been reused, treated, and piped into the water supply a number of times before the last downstream user withdraws the water” (EPA).

“Planned projects are those that are developed with the goal of beneficially reusing a recycled water supply,” often put into place to accommodate an expanding community’s water needs (EPA).

Recycled, treated wastewater is utilized in “agricultural and landscape irrigation, industrial processes, toilet flushing, and replenishing a ground water basin (referred to as ground water recharge)… cooling water for power plants and oil refineries… construction activities, concrete mixing, and artificial lakes,” saving resources and money simultaneously (EPA). Recycled water must meet certain requirements before it can be reused in these ways, and the EPA claims there have been no negative results from the current use of recycled water. The aforementioned uses for this recycled water are considered non-potable purposes—not for drinking.

The EPA defines “Gray water” as “reusable wastewater from residential, commercial and industrial bathroom sinks, bath tub shower drains, and clothes washing equipment drains. Gray water is reused onsite, typically for landscape irrigation.”

Between July 2011 and July 2012, San Marcos’ population increased by 4.9%; the city’s total population soon surpassed 50,000 (U.S. Census Bureau). According to the United States Census Bureau, Hays County’s population was estimated to increase by 5.2% between July 1, 2014 and July 1, 2015. If the population continues to grow, the demand for water will alongside it.

To prepare for this growing need, it is essential to look toward other communities that are already implementing new methods to make the most out of their water. The EPA presents the following example: “the City of Tucson, AZ adopted an ordinance in 2008 requiring that: All new single family and duplex residential dwelling units shall include either a separate multiple pipe outlet or a diverter valve, and outside ‘stub-out’ installation on clothes washing machine hook-ups, to allow separate discharge of gray water for direct irrigation; all new single family residential dwelling units shall include a building drain or drains for lavatories, showers, and bathtubs, segregated from drains for all other plumbing fixtures, and connected a minimum three (3) feet from the limits of the foundation, to allow for future installation of a distributed gray water system; all gray water systems shall be designed and operated according to the provisions of the applicable permit authorized by ADEQ under the Arizona Administrative Code, Title 18, Chapter 9.”

Even though the use of gray water is both “a sustainable approach and can be cost-effective in the long term,” there are “Institutional barriers, as well as varying agency priorities and public misperception, [that] can make it difficult to implement water recycling projects” (EPA).

As San Marcos will have to continuously accommodate for its growing population, it will be crucial to break these barriers by remedying the public misperceptions surrounding non-potable water.

“Advances in wastewater treatment technology and health studies of indirect potable reuse have led many to predict that planned indirect potable reuse will soon become more common. Recycling waste and gray water requires far less energy than treating salt water using a desalination system,” suggests the EPA.

At this point in time, the City of San Marcos receives two thirds of its water from “raw surface water” derived from the Guadalupe River (Canyon Lake), “treated at the Surface Water Treatment Plant (SWTP) under the operation of the Guadalupe-Blanco River Authority (GBRA).” San Marcos truly depends on the SWTP as over two million gallons of surface water are treated over the course of a year (City of San Marcos, SWTP, 2008). 75% of the City’s potable water is sourced in this way, while the other 25% is acquired through several groundwater sources.

Although San Marcos is supported by both federal and local organizations, its security is not infallible. As the City continues to draw in individuals, families, and prospective students, its natural resources could be strained. To ensure water is utilized fully and resourcefully, citizens should reassess the potential of gray and recycled water.