By Josh Davis
Water has played an important role in Houston’s infrastructure and growth since the city’s inception in 1837 when the town was born at the junction of the Buffalo and White Oak bayous. Although the trip was arduous, the ability to navigate the bayous from the Gulf of Mexico allowed the town to prosper and rapidly increase in population through its early years.
Flash forward to today and Houston is the fourth largest city in the United States, with over 7 million residents in the metropolitan statistical area. Most projections indicate that if the city continues to grow at a similar rate to last two decades, the Houston area will be home to over 10 million residents by 2050, with many projections indicating much higher growth than that.
For a city that was founded in part because of its access to water for commerce, and one that has demonstrated its strength and determination through disastrous flooding events, water will continue to play an important role in the prosperity of Houston, but not necessarily only in the ways previously mentioned. A huge opportunity for Houston lies in its ability to effectively handle the scarcity of water and provide it as a drinkable resource for the huge growth in population that is expected to continue. Before we talk about how the City of Houston is handling their growing population and the demands that growth has on the water supply, let’s take a look at the water infrastructure throughout the United States as a whole.
America’s Water Infrastructure
Whether it’s considering the estimated 650 water main breaks a day, countless miles of leaking supply pipe (or worse yet, sanitary sewers), environmental compliance issues faced by numerous treatment facilities, or land subsidence and drained aquifers, reports have been pouring in about America’s aging water/wastewater infrastructure for years. While conservation efforts have intensified and data shows that we are more conscientious than ever before, the inefficiencies, dilapidated conditions, and outdated technologies of typical water and wastewater infrastructure are reaching critical levels. The most recent National Infrastructure Report Card from 2017 rated Drinking Water infrastructure at a D and Wastewater infrastructure at a D+. The report is alarming especially as we face increased environmental concerns and funding issues that jeopardize future projects and water sustainability.
There are solutions but improving the National Water Infrastructure begins with funding. All told, an estimated $1 trillion is needed over the next 25 years to meet increased water demands. Projects that entail expanding, rehabilitating, upgrading, or creating new plants and infrastructure while utilizing innovative/sustainable solutions to maximize and improve water services are a must. When combined, the need for funding and innovation within projects provides an opportunity for cities to build value.
Everything’s Bigger in Texas
Although the outlook on water/wastewater infrastructure in America could use improvement, there are some bright spots throughout the nation that showcase the potential for combatting the water needs of the future. Houston is on the leading edge of tackling this issue. The city is in the process of shifting from its reliance on groundwater to surface water as the source for what the growing population will use. A critical part of this shift is the $1.765 billion expansion of the Northeast Water Purification Plant (NEWPP), which just so happens to be the largest progressive design-build water treatment plant project underway not only in Texas, but in the entire United States. The original NEWPP plant could handle roughly 80mg/d but this expansion will add 320mg/d to the water supply. This will allow Houston to have the ability to grow for decades to come.
The team taking on the NEWPP Expansion consists of a joint venture between Jacobs and CDM Smith called the Houston Waterworks Team (HWT). HWT divided the work out into various packages, with McCarthy Building Companies, Inc. being awarded three separate contracts on the project.
The first of the three work scopes consists of the Early Works Central Plant Foundations package. This work involves furnishing as well as installing all rebar and structural concrete, embeds, pipe penetrations, and under-slab process mechanical piping on the west Filter Module and Transfer Pump Stations. The mechanical piping consists of over 15 miles of pipe, with diameters ranging from 2 inches all the way up to 108 inches, all self-performed by McCarthy’s skilled workforce.
The second work package that McCarthy is performing includes the construction of a 30,000 square foot raw water Intake Pump Station (IPS) located in the middle of Lake Houston. The IPS consists of ten submersible pump cans which hold the pumps that will draw water from the lake and send it to the plant for processing. The entire structure is built on steel piles, with a 1,000-foot approach way consisting of precast concrete caps and a precast concrete deck, which holds two separate 108-inch diameter water lines that move the water towards the plant. McCarthy floated the large diameter pipes out to the platform on barges. Additionally, they completed the pile driving and concrete deck of the structure first in order to maintain a tight schedule and allow mechanical work above the deck to continue. McCarthy then floated the in-line submersible pumps under the deck with inflatable bags. Once positioned, they deflated the bags and sunk the pumps into the pump cans, utilizing divers and wenches on embeds cast into the deck above. This creative approach was successful and allowed the project to move along smoothly.
The third package includes the balance of construction of the Central Plant, which will consist of a full buildout of the two facilities already underway as part of the early works package to complete Phase 1. Additionally, the package includes the rest of the filters, the second Transfer Pump Station, and post-chemical facilities for Phase 2. With the completion of both Phase 1 and Phase 2 of the Central Plant, the filters being installed are the largest in the state of Texas. Each building contains twelve filters, together housing a total of twenty-four filters with a volume of over 10 million gallons.
A Bright Future
As the United States continues to grow in population, the cities that combat the issue of sustainably harvesting natural resources like water will continue to prosper. The City of Houston’s proactive approach to addressing the aging infrastructure and the expansion at NEWPP is just one piece of the city’s comprehensive plan that will address the needs of a growing population for generations to come.
Josh Davis has been with McCarthy for seven years, with the majority of his time being spent in the Houston area. He has held various positions with McCarthy in the field and now works in Business Development in the Heavy Civil, Marine and Industrial business unit.