Study eyes economic impact of Lake Conroe's lowering levels

George Rogers

George Rogers

Sam Brody

Sam Brody

Georgianne Moore

Georgianne Moore

Jesse Saginor

Jesse Saginor

Though ranked as one of the fastest growing counties in the nation for the last two decades, groundwater-dependent Montgomery County, Texas is confronted with a looming water crisis that threatens its future growth, according to a recent study by urban planners at Texas A&M University.

The study investigated how increasing regional demands for water from Lake Conroe, the county's primary surface water source, and resulting reductions in the recreational lake's water level might impact the area's economy. Though researchers found that anticipated lower lake levels present a threat, limited primarily to the lake-area economy, they said the impending regional water crisis poses a more significant peril to the county's longstanding prosperity.

To mitigate the threat, the study urges county water management authorities to institute immediate, proactive water conservation measures as they seek to diversify their water resources and negotiate an authoritative voice in how the lake's water is used.

Groundwater depletion

Though home to the 20,100-acre lake, Montgomery County is facing imminent water shortages because its growing population relies almost exclusively on freshwater aquifers, or groundwater, for its water supply, and those sources are being depleted faster than they can recharge, explained George Rogers, professor in the Department of Landscape Architecture and Urban Planning at Texas A&M University and the study's principal investigator.

Further confounding the issue, water rights to Lake Conroe are controlled by the San Jacinto River Authority and the city of Houston, which has long owned a two-thirds share of the water, but only recently began to draw it from the lake.

Though the SJRA has a Groundwater Reduction Plan in place to provide lake water to the county's groundwater-reliant municipal utility districts, most agencies have yet to negotiate the acquisition of water rights or invest in the estimated $200 million infrastructure needed to process the surface water and facilitate its distribution.

Montgomery County, as shown the 2000 and 2010 U.S. Censuses, has benefited from dynamic growth. However, "this growth is fundamentally related to the economic health of the county," the study notes, and "is not sustainable without water. The current reliance on historically used freshwater aquifers, as the sole source of water is rapidly becoming a limitation on the future growth of the area.”

The need is urgent. The Lone Star Groundwater Conservation District estimates Montgomery County will require 154,000 acre feet of water per year by 2040, but the state will limit ground water withdrawal to 64,000 acre feet beginning in 2016. To adjust for this projected 90,000-acre-feet shortfall, LSGWCD proposes that existing and future water providers find alternative water resources to make up for what would be a 30 percent reduction in groundwater pumping from 2009 levels.

In addition to strong water conservation measures — required by the SJRA for water providers enlisting in its Groundwater Reduction Plan — the Texas A&M study also suggests that water agencies pursue other surface water resources within the San Jacinto and Trinity river basins and consider using water from alternative aquifers offering lower quality water that, like surface water, will be more expensive to process.

"These diverse sources of water may prove essential as part of a long-term solution," the study notes.

Scope of the study

Assisting Rogers with the research were co-principal investigators Sam Brody and Jesse Saginor, both fellow LAUP faculty members, and Georgianne Moore, associate professor of ecohydrology at Texas A&M. Project researchers included Gabriel R. Burns, an Urban and Regional Science Ph.D. student, Theepakorn Jithitikulcha, an Agricultural Engineering Ph.D. student, and Travis Young, a Master of Urban Planning student.

The research team reviewed and evaluated existing lake-level studies and examined how fluctuating lake water levels — particularly lower levels — affect the surrounding property values and sales tax revenues. Additionally, lake area residents and business owners were surveyed to evaluate how lower lake levels influence commerce, public perceptions and behaviors.

The Texas A&M study was undertaken to provide independent objective information to aid decision makers and local leaders in water policy and strategic planning. The research was primarily funded by the Lake Conroe Communities Network, with additional funds from Montgomery County and other local government and community agencies.

Lower average lake levels expected

The study was conducted, in part, during the 2011 statewide drought, which saw Lake Conroe water levels drop as far as eight feet below the full pool level of 201 feet, alarming lake area residents, lake-dependent businesses and the lake's recreational users while raising public concerns about the lake's future — unease compounded by ever increasing demands for the lake water. The historically low water levels in the shallow lake receded the shoreline, left docks grounded in the mud and made the recreational waters treacherous for boaters.

Though mostly recovered, on Aug. 13, 2012 the lake remained 2.45 feet shy of full pool. However, future lake-level scenarios put forth in a 2010 study performed for the SJRA and reviewed by Texas A&M researchers, project consistently lower levels than historically experienced. The various projections, based on historic lake-level patterns, factor in increasingly greater water extraction as local municipal utility districts join the SJRA's Groundwater Reduction Program, but do not account for lake water use by the city of Houston or for a potential increase in the frequency and/or duration of drought conditions.

The 2010 study does suggest that future droughts will result in lower lake levels on average and more frequent lake level drops, which will remain low for longer periods compared with the similar-sized droughts in the past.

"From 1974 to 2008, lake levels as low as four feet below full pool occurred 2.8% of the time," the study reports. In the future, under the four GRP scenarios accounting for additional annual lake water diversions in 25,000 acre-feet increments, levels four-feet or more below full pool are expected to occur with increasing frequency — 4.6% (-25,000 ac. ft.), 7.9% (-50,000 ac. ft.), 12.7% (-75,000 ac. ft.) and 22.0% (-100,000 ac. ft.) of the time.

Low lake levels hurt lake-area economy

Economically, these scenarios do not bode well for lake area property owners, lakefront and lake-dependent businesses and the nearby city of Montgomery, which, according to the Texas A&M study, will be most negatively impacted by low lake levels. On average, survey respondents reported negative experiences from lake levels three feet below average and most marinas interviewed said boating and lake accessibility issues emerged at two feet below normal lake levels.

In short, lake area business owners surveyed in the study indicated that "continued low lake levels are not sustainable for local businesses."

Texas A&M researchers characterized the lake level projections from the 2010 study done for the SJRA as reasonable and even conservative, but also noted that a more comprehensive study is needed to account for current and projected hydrologic changes associated with urbanization of the region, increasing lake-bottom sedimentation and authorized water usage beyond the GRP projections, such as that by the city of Houston.

"Given that drought will continue to be an issue for Lake Conroe," researchers said, "we recommend a comprehensive study aimed at predicting and planning for future drought scenarios."

Though persistently lower lake levels and dramatically lower levels experienced during droughts will likely have a significant negative impact on lake area businesses and property values into the future, researchers found that these adverse economic consequences rapidly diminish throughout the county with geographic distance from the lake. Montgomery County's strong, diversified economy is resilient overall, the study reports, and able to withstand and absorb the repercussions that impact the lake area economy.

Survey results characterize Lake Conroe area residents as exceptionally resilient and able to adapt to the lake's evolving character. On the other hand, respondents, on average, were extremely concerned about the increasing fluctuation of lake levels, preferring the stability they've experienced in the past, but anticipating persistently lower levels in the future. Lake area property owners surveyed in the study noted that foreseen lake level changes have reduced neighborhood property values as much as 28% and they anticipate greater reductions as the lake level diminishes. Approximately 55% of the survey responders reported neighbors who were putting their homes on the market as a result of the lake level projections. 

County needs input in lake matters 

Numerous respondents were not aware that the city of Houston had access and control of Lake Conroe's water and some said they would not have purchased lakeside property had they known the city could draw water as needed.

The study found that Lake Conroe area residents were frustrated by their lack of input in the governance and operational control of lake's water and were united in their desire for county officials to play an active role in lake water management.

In response to these concerns, the study's authors urge Montgomery County officials to find mechanisms to exert their views into the lake's operational matters. Suggestions include negotiating an ownership share in the lake, working toward identifiable role on the SJRA board, or enhanced proactive participation in SJRA activities and decisions.

"Though receding shorelines pose significant and perhaps inevitable economic issues for the Lake Conroe area, the bigger threat to Montgomery County is its dwindling groundwater resources," Rogers said. "Our study shows that immediate and decisive action is needed to diversify the county's water resources and assure a prosperous and sustainable future for the region."

posted August 14, 2012