Higher water bills and traffic congestion are two consequences The Woodlands residents are experiencing because of the San Jacinto River Authority's Groundwater Reduction Plan. However, without SJRA's plan—which could begin pumping surface water from Lake Conroe in June 2015— Montgomery County would continue to use more groundwater than its aquifers can refill, eventually causing damage to the county's environment and infrastructure, hindering future development and leading to exponentially rising water costs.

"Montgomery County is one of the fastest growing counties in the United States, and we're all happy about that," said Mark Smith, manager of the SJRA's GRP division. "At the same time that is going on, the water level of the aquifers is dropping every year. We're depleting the water supply. So, what happens to this wonderful economic growth we're experiencing if we run out of water?"

Groundwater overuse

Montgomery County receives its groundwater from the Gulf Coast Aquifer System. Unlike other aquifers across the state that refill relatively quickly following rain, the local aquifer system requires far more time to refill, said Kathy Turner Jones, general manager of the Lone Star Groundwater Conservation District.

"We're talking thousands of years for one drop today to get back to our aquifer system here," Jones said. "It's a slow process."

The conservation district determined the county's current usage of the aquifer system is not sustainable. Montgomery County water users pumped more than 102,000 acre-feet of groundwater in 2013, while only 64,000 acre-feet of groundwater is refilled to the aquifers within Montgomery County every year through long-term rainfall.

The fourth fastest-growing county in the state, Montgomery County's population is expected to surpass more than 1 million people by 2040, Jones said. The water demand of the county's population will climb to more than 140,000 acre-feet per year. If alternative sources of water are not found, the amount of water within the local aquifers could fall by hundreds of feet, she said.

Subsidence

Perhaps the greatest danger of groundwater overuse is subsidence, which occurs when clay layers within the aquifer compact and settle, lowering the ground surface area from which the water is being pumped. Jones said subsidence can lead to flooding, structural damage and well damage. It could also decrease the amount of available groundwater across the region.

Jones said there have already been some minimal signs of subsidence in Willis and The Woodlands.

"Subsidence is always a huge potential," she said. "I think we can look at our neighbors to the south [in Houston] and realize they are an excellent example of getting into a situation where disaster was occurring on the coastal areas and even more into the metroplex where they had land subsidence in significant amounts."

Groundwater scarcity could also hinder development as developers require available, sustainable water sources before purchasing land for possible construction.

Groundwater reduction plans

To address groundwater scarcity, the LSGCD began establishing rules and regulations in 2006 for water users, Jones said. A mandate was implemented requiring water users to reduce their annual groundwater usage by 30 percent of their 2009 total by Jan. 1, 2016. Although there are 33 groundwater reduction plans countywide, SJRA's plan accounts for about 80 percent of large volume groundwater users across the county, Smith said.

"When Lone Star came up with the regulations, we had to come up with a plan," Smith said. "We looked at alternatives with how we would comply with Lone Star. We have this water resource here. We own a third of the water in Lake Conroe, and can we use that as a way to meet our mandate?"

Knowing Lake Conroe contained more than enough water to meet the needs of the region, SJRA crafted a plan to pump surface water from the lake to users throughout Montgomery County, Smith said. Rather than supplying surface water to participants of the groundwater reduction plan, however, the SJRA opted for a cheaper option and will pump more than the required amount of surface water to a handful of municipalities and utility providers to meet LSGCD's mandate.

Conroe, The Woodlands, Oak Ridge North, the Rayford MUD and the South Montgomery County MUD are the only participants within SRJA's plan that will water from Lake Conroe. Those users will reduce their 2009 groundwater usage by 60 percent rather than the mandated 30 percent to offset the groundwater use of the plan's other participants who will not receive surface water.

Once the 55 miles of pipeline and a surface water treatment plant are constructed, SJRA will begin pumping surface water as soon as June 2015—six months prior to the 2016 deadline—to test the system and begin reducing the region's dependence on groundwater. Phase I of the plan will allow water users to pump up to 30 million gallons of surface water per day and drain about 1 foot of water from Lake Conroe per year.

"Most people don't realize that Lake Conroe is a water supply reservoir," SJRA Public Relations Manager Ronda Trow said. "The reason this reservoir was built back in the 1950s—when they went through the five-year drought—was for the purpose that we are finally using it. Because we had people way back when who had the foresight to think, 'Eventually we could run out of water, so let's build this water supply reservoir so we don't have to worry about this.'"

Smith said the SJRA is still working on a drought contingency plan for all of the plan's participants, which would enforce conservation procedures on surface water users once the lake reaches certain levels. Smith said the SJRA could vote on the plan in May.

In the next 20-plus years, the SJRA may construct a pipeline system from the Trinity River to Lake Conroe to supplement the reservoir, a project that could cost hundreds of millions of dollars. Smith said the SJRA already pays $300,000 per year for a contract with the Trinity River Authority that could allow them to pump up to 50,000 acre-feet of water from the river every year.

Alternative sources

Although the main focus of SJRA's plan is to use surface water from Lake Conroe, Smith said the SJRA would examine all sources of water to meet LSGCD's mandate.

"Our mission is not to drain Lake Conroe; our plan is to meet the mandate or to offset the demand for groundwater in Montgomery County," Smith said. "It's [about] developing alternative water supplies, and we're open to all alternatives."

Smith said the SJRA is considering re-using treated water from wastewater treatment plants for irrigation and studying the Catahoula Aquifer as another alternative source. Jones said other groundwater reduction plans countywide are already relying on the Catahoula—a deep aquifer within the Gulf Coast Aquifer System—as a source to meet the district's mandate.

The city of Shenandoah has partnered with Panorama Village, helping Panorama pay for a well within the aquifer to offset the city's own groundwater use.

Jones said re-use of existing water is another alternative that can be further explored in the future. The Woodlands already re-uses water for irrigating of some golf courses, she said, while local developers could be considering re-use as an alternative source.

"[The ongoing development at] Camp Strake, I'm sure that there's more they can do to look at maybe a direct re-use project there on common areas or if they're looking at any amenity-type features," she said. "They can use that type of source rather than using well water to fill up a lake."