The city of Houston has a strong connection to its bayous. The term was used in 1763 to describe the sluggish usually marshy bodies of water in the southern United States(1). Bayous are created in low lying areas, where elevation change may be very slight, or when ocean tides reverse flow of water (2). Houston is estimated to contain 2500 miles of bayou waterways, Buffalo Bayou is the most prevalent with a strong connection to Houston’s history. With its rise at the juncture of Willow Fork and Cane Branch, west of Katy, TX, the Buffalo Bayou runs sixty five miles east across Harris County, through current day Houston, to the San Jacinto River where it experiences tidal activity (3). In 1836 brothers John K. Allen and Augustus Allen bought 6,642 acres along the Buffalo Bayou intending to make it a seat of government for the newly independent Republic of Texas (4). The Allen brothers understood access to a thriving town requires drinking water and therefore totted the presence of Buffalo Bayou as a staple provider of resources to early settlers (5).
Early settlers also found other sources of water in rain collection, storing bayou water, and groundwater wells and springs. One such groundwater source was Beauchamp Springs noted as being “pure, cold, and wholesome water,” Beauchamp Springs potentially consisted of four different springs, one named Riordan’s Spring thought to be an inexhaustible supply of pure water (5,6). Located about a mile and a half outside of the growing Houston area, water was collected at the spring in 30 gallon barrels, delivered by wagon, and sold to people for seventy-five cents per barrel (5).
The Houston Water Works Company, a private company contracted by the city, was founded in 1879 to provide continuous flow of water for general purpose, drinking, and most importantly firefighting (7). Pumping water directly from Buffalo Bayou, the company was tasked to provide 55 hydrants, 150, 000 gallon reservoir, 3,000,000 gallons of water a day, four miles of distribution piping (5). In 1887, Henry Thompson discovered a large underground reservoir, which the Houston Water Works Company proceeded to drill 14 wells into, making the switch from bayou water to the much cleaner groundwater.
However to maintain pressure, especially during firefighting activities, the Water Works Company used bayou water. Aquatic life and sewage contamination were noticed in the drinking water, and citizens became disturbed by the company’s claim of supplying pure potable water (7,5). The city of Houston bought the Houston Water Works Company in 1906 for $901,000, drilled 66 new artesian wells, and returned the entire distribution system to groundwater sources (5).
As the population grew, so did the demand for water, city officials began thinking about possible alternatives to groundwater to meet the needs of the city. Surface water rights were purchased for lakes and rivers including the San Jacinto, dammed to create Lake Houston and Lake Conroe, and the Trinity River, dammed to create Lake Livingston. Over the years three water purification plants have been built to treat the surface water, the first was the East Water Purification Plant in 1954, second, the Southeast Water Purification Plant in 1989, and lastly the Northeast Water Purification Plant in 2005 (8). In, 2016 the city treated about 439 million gallons of water per day or 160 billion gallons per year (9).
Geography of Houston
The city boundaries of Houston, TX are at best complicated. Below is a map of Houston; areas enclosed in a red outline or shaded in red have an address which denotes Houston, Texas as the city in their respective address outline . Locals define the city areas as the “inner” and “outer” loop. Interstate 610 (I-610) forms a loop around what is considered the downtown area of Houston. Texas State Highway Beltway 8, forms an “outer” loop, about 5 miles outside of I-610. For simplification purposes, many Houstonians consider this physical landmark the city limit by.
Figure 1: Map of Houston City Limits (10)
The city of Houston and surrounding suburbs are noted as being fairly flat. The top elevation in Houston is 128ft in a northwest suburb (11) downtown Houston is about 50ft above sea level. Due to excessive groundwater use, parts of the city are sinking, in some areas as much as 9 to 10ft, causing issues with drainage (12) .
The number of wetlands in Houston has decreased by an estimated 50% in the last 25 years to make way for this rapidly expanding city. Urbanization affects drainage, as water can no longer run off into the surrounding area bayous. Once natural areas flood, the freeways of Houston act as secondary flood control (11). If water overflows the freeways, residential areas begin to flood. With the combination of little natural drainage, flat topography, and drainage damage due to sinking land, flood waters are a major problem for Houston.
Houston Municipal Water
The majority of Houstonians receive drinking water managed by the Drinking Water Operations (DWO) Branch of Houston Public Works. The DWO runs six community public water systems, their names and approximate population served are as follows: Main (2.3 Million), Willowchase (13,500), Kingwood (78,000), District 82 (740), District 73 (4,400), and Belleauwoods (800). All systems are supplied by groundwater with the exception of Main, which receives 85% of its water from surface sources, and Belleauwoods which Houston purchases 94% of the water supplied from Humble, TX where they use both surface and groundwater. Houston has three water purification plants and a total of 56 groundwater plants. All three of the purification plants supply the Main system, as well as 40 out of 56 of the groundwater plants; the remaining 16 plants serve the other five Houston water systems (13).
Source: Houston Water Quality Report: January- December 2016 (13)
Surface water is supplied from the Trinity River which flows south from Lake Livingston and the San Jacinto River which flows south from Lake Conroe and Lake Houston. All three of these lakes are man made via dams to create an ample reservoir of supply water. Much of the groundwater is pulled from Evangeline and Chicot aquifers with well depths greater than 750 feet, averaging 1,200 feet. Due to the serious land subsidence problems experienced, the state has mandated the reduction of groundwater usage, with an allowable maximum pumpage of 20% (5).