Safeguarding Scarce Resources
Employing new tricks and old standbys as part of a water resource plan that identifies risks, uncovers threats, and is designed to prevent future disasters
For more than 70 years the Equus Beds Aquifer has been a major source of water for the City of Wichita, KS, but that does not necessarily mean that the next 70 years will be just fine, too. The wise people of Wichita have initiated the Aquifer Storage and Recovery (ASR) Project to ensure that good water is available for at least another 40 years. The aquifer is about 1,400 square miles, with the average withdrawal 157,000 acre-feet. It has been recharged every year (so far) by natural, seasonal precipitation and surface water infiltration. About 20 years ago, however, it was determined that the aquifer was being weakened by pumping that exceeded its natural recharge capacity. This was the most important stage of the resource management—the time when the authorities realized that their water supply could run out or become unhealthy.
The aquifer covers parts of several Kansas counties, including Harvey, McPherson, Reno, and Sedgwick. Municipalities served have been Wichita, Halstead, Hutchinson, McPherson, Newton, and Valley Center. They take some 39% of the water. The irrigators in that region use 55%, and industry 6%.
The threat perceived was not just the shortage of water—it was also the quality of the water. The excessive usage threatened an influx of saltwater from the Arkansas River (to the southwest) and oilfield brine (from the northwest). If no changes were made and the Equus Beds was not replenished, the average chloride concentration in the groundwater would increase levels, making it unsuitable for either drinking or irrigation. In plain terms, that meant that 94% of the water’s use would be unsafe.
| Photo: BURNS & MCDONNELL
| How an artist envisions new water facilities for the City of Wichita
For the current phase of this future-strengthening project, there is a joint-venture team designing and constructing a river intake with capacity to withdraw up to 68 million gallons per day (mgd) and an interconnected 30-mgd water treatment, storage, and pumping facility. The joint venture includes engineering, architecture, and consulting firm Burns & McDonnell (based in Kansas City, MO), Alberici Constructors (from St. Louis, MO), and CAS Construction (from Topeka, KS). The city chose that team in April 2009 to provide engineering design and construction services under a $74.2-million contract. That contract showed a savings of $28 million over initial project estimates. “This project is among the largest and most complex aquifer recovery programs currently underway in the United States,” notes Dave Kress, vice president of Alberici’s Water/Wastewater Division.
“We have a long-term relationship with the City of Wichita,” comments Jim Foil, senior vice president at Burns & McDonnell. “It goes back many decades, so we have a deeply vested interest in helping the community meet its water security needs.”
What are the projected benefits of this water resource management? It will add up to 70 billion gallons (214,000 acre-feet) of water to the aquifer, in order to meet the demands of the City of Wichita during periods of drought. It will protect the aquifer from water-quality deterioration by creating a hydraulic barrier to halt—or stop—the intrusion of natural and manmade sources of saltwater. It will also reduce the power cost for pumping, both Wichita and other users of the water, because of the higher groundwater levels created.
The engineering and construction involved in the City of Wichita’s plans for future stability in water resource management are most commendable, but the key to success may have been the work done and decisions made in 1993. In that year, the Wichita City Council adopted an Integrated Local Water Supply Plan that identified cost-effective resources that would be enough to meet Wichita’s water supply needs through the year 2050. No matter their size, cities, counties, or communities can relate with the problems Wichita anticipated. The population served by Wichita’s water utility would jump from 335,000 mgd to 558,000 mgd—that’s almost double. The increases in water demand for an average day would rise from 62 to 125—double again. On peak days, the increases in water demand would go from 125 mgd to 250 mgd—double, too. Clearly, the solution was not to say “Oh dear”, and hope the rainfall would increase.
The City’s plan, rather than relying on one water source (like a reservoir), selects a variety of water resources. There’s the ASR project mentioned above, a better use of the Cheney Reservoir, expansion of a local well field by the Arkansas River, development of high chloride water wells by the Arkansas River, and better water conservation. The lesson? Start today to research the future needs of the community and start doing something about it. The alternative is frightening—no good drinking water and costs higher than imaginable.
Looking at the Whole Picture
It is difficult, as a public works manager of a small or, even, medium-sized community, to see how the outlook for the entire country can affect one community, as well as to see how programs that larger authorities can afford may be able to help. Don’t despair. Projects that are similar, but smaller than those described for Wichita, may be able to help, as there may be a local solution that draws inspiration and ideas from larger water utilities. In that respect, there’s a white paper by Maureen Duffy, of American Water, that is worth reading and digesting. American Water is the largest, investor-owned water utility in the US, serving more than 15 million customers in 30 states. The company has a good history of cooperation with municipalities as well as in its independent services. In the white paper, entitled Integrated Water Resource Management (IWRM), Duffy brings up many interesting, challenging ideas.
“IWRM is the management of the whole hydrologic cycle to achieve a coherent set of water resource policies and uses the balances of all reasonable social, environmental, and economic needs in a sustainable way,” says Duffy. “Providing safe, reliable, and cost-effective service increasingly means a more holistic approach to water resource management. The better all the elements are managed, the better the impact on safety, reliability, and cost.”
Here’s wisdom in a nutshell: It doesn’t say there needs to be a million customers to do it. The elements one may consider in the approach are watershed protection; wastewater management; reuse; stormwater; source of supply constraints; ecosystem and environmental protection; and conservation, groundwater infiltration, and recharge.
“Water utilities can lead the way by developing policies and practices that promote the preservation and restoration of water resources and by fostering strategic partnerships to use [collaboratively] integrated water resource planning and management as a tool to examine assumptions concerning supply, demand, and alternative methods of meeting unmet future demand and social, economic, and environmental challenges,” asserts Duffy as a positive suggestion for future work.
To recap, the IWRM principles recognize that fresh water is a finite, but renewable and vulnerable resource, essential to sustain life, development, and the environment. We should manage water resources based on watersheds and needs of relevant stakeholders. We should preserve water courses and use water wisely. Allocate water equitably based on input from all relevant stakeholders. This can be a local policy, but wouldn’t it help the country if it were national?
The whole picture of a community’s water resource management shows not only what should be available for everyday, normal situations, but also what can be done to alleviate the problems brought on by unusual weather conditions. For example, look at this year’s weather, in almost every part of the country, to develop a different concept of what “unusual” conditions can occur without notice, without warning, and often without a good plan about how to defeat them. One of the goals of The Freeport Regional Water Project in California has been to provide a safety net (to the tune of 100 mgd) for the 1.4 million residents of the Easy Bay area should there be a serious drought, which can happen in three of every 10 years.
The Freeport Regional Water Project has been about 35 years in the making and is the result of a landmark agreement between the East Bay Municipal Authority District (EBMUD) and the Sacramento County Water Agency (SCWA). Apart from that safety net for the East Bay Area, it will provide up to 100 mgd of water to southern Sacramento. Brown and Caldwell has played a leading role in the engineering of the project. The Freeport facilities start with a new Sacramento River intake and Pump Station followed by a 16-mile, 84- to 66-inch pipeline (half designed by Brown and Caldwell). The pipeline includes 10 tunnels, a flow control facility, and a bifurcation/surge control facility to deliver water to South Sacramento’s new Vineyard Surface Water Treatment Plant. That plant treats surface water from the river and supplies it to the SCWA customers. With the Freeport Regional Water project in operation, SCWA will be able to supply water to more than 40,000 customers. If this project emphasizes one aspect of large-scale water resource management, it is the need for planning and cooperation between all parties involved. There were strong legal challenges when the project was first proposed, some from those who feared the new water supplies would drain the river (and defeat its purpose), but good cooperation between communities and water districts have produced a solution that promises to be both efficient and long-lasting. This is where the involvement of skilled, experienced engineers, such as Brown and Caldwell, is so important. Such a successful project reminds us that most communities, water districts, municipalities, and water utilities will probably need genuine expert help when planning the future. That expert may not be local, but may have experience in many projects over many years and is certainly worth consideration before rare dollars are spent on projects that are not adequately researched and engineered.
Aids to Better Management
Information about what we have and what we’ll need in the future, depending on both population growth and availability of reliable sources of water, is of vital and obvious importance to everybody involved in the management of water resources. That information will also include facts about the efficiency of our current plants and programs. One of the leading suppliers of software that will ease the task for water managers is AllMax Software, Inc.
“The world’s water is a vital resource that must be protected and managed to ensure continued usability,” assets Russell Maxwell, President and CEO of AllMax Software. “As we continue to refine the science of water treatment and reuse, an infinite amount of data will be generated that can be analyzed to improve the accessibility, quality, and sustainability of our world’s most important resource. This massive amount of data has the potential to become unmanageable unless steps are taken to improve upon the processes that utilize and manipulate this data. Your solution is a reliable management system.”
Wheeling Water Department in Wheeling, WV, is an independent, municipally owned water utility that serves about 50,000 people. The utility has three divisions, responsible for all treatment and testing of the source, finished water, and for pumping it to the customers. It treats some 7.5 million gallons of water per day and distributes this water through 200 miles of water mains. Data had always been entered and managed manually by the operators and plant manager. Now the Wheeling water department relies on Operator10 from AllMax Software.
“Our department pays an annual maintenance fee for the software, which entitles us to any software upgrades or revisions,” notes Phil Kowalski, Wheeling’s plant manager. “In addition, we have access to their excellent online support. Operator10 is easy to navigate and offers four separate operations packages [water, wastewater, biosolids, and pretreatment], which may be purchased separately or together.”
Features include an audit trail expanded field sizes, data permissions, improved scheduling, undo/redo, intermittent DataViews, an improved interface for linking to any SCADA (Supervisory Control and Data Acquisition) and other applications, a new section for recording sampling events, and a redesigned report section. “The ability to have data on water-quality and chemical feed parameters in a format that allows flexibility for trending and graphing for the past 20 years gives our operating staff the ability to make decisions on water treatment based on past practice,” adds Kowalski. “This allows us to compare quickly treatment schemes that worked effectively for a given set of raw water conditions.”
Data management software plays a vital role in the process of managing water resources and allows operators and managing directors the ability to make important, informed decisions. “Municipalities need to establish a means to store and manage vast amounts of entered, collected, and calculated data, and solutions for generating data for reporting and graphing for all users,” comments Brian Sprang, Technical Support Specialist at AllMax Software. “Centralized data storage helps to eliminate the difficult process of finding key data across different users’ computers or storage locations. Stored and reusable entry tools, graphs, and reports help to minimize the time from collection to output, especially in the case of agency-based reporting, which may occur monthly. Customized data point creation allows the user to define fully a treatment process as it exists in the real world. The right software program provides the tools to bring the calculation of plant performance information that much closer by providing standard water- and wastewater-based math.”
The Suwannee River Water Management District (SRWMD) in North Central Florida is one of five regional water management districts in Florida and covers about 7,650 square miles, including all or part of 15 counties in north central Florida. SRWMD contracted Cardno ENTRIX (water experts with offices in over 150 countries) to prepare a district-wide Water Supply Assessment Report and a Regional Water Supply Plan for the Upper Santa Fe River Basin. Cardno ENTRIX is developing detailed 20-year population and water use demand projections for the whole district to assure the adequacy and sustainability of water supplies in the SRWMD. The researching company will use the water use demand projections to update the district’s regional groundwater flow model to determine the availability of groundwater supplies in five-year increments for the 20-year planning period. At the same time, Cardno ENTRIX is working to assess environmental constraints on the water resources of the district; it will determine at what point in the future such constraints may be activated if conventional water supply sources are used. This constraint analysis will allow Cardno ENTRIX to investigate, identify, and provide preliminary costs to develop sustainable, alternative water supply resources for SRWMD. That could include desalination of brackish groundwater, collecting surface water from rivers during high-flow periods, and using reclaimed water to offset irrigation needs. Such alternative supplies can protect wetlands, vegetation, springs, and surface water levels to counteract the negative impacts always associated with groundwater over-pumping.
There’s more to the preparations by these water experts, and it must reinforce the theory that every community, big or small, can benefit from the experience and expertise of such groups as Cardno ENTRIX. In Florida, they are also devising water conservation strategies and potential funding sources targeted at agricultural and public water supply users. Other simultaneous investigations include mitigation and protection strategies to help SRWMD deal with the predicted effects of climate change in the region.
Is It All Worth It?
The foundation of efficient water resource management is information, accurate data about what we have, what we are doing, and what we could be doing to be better. Today, accurate information comes via computers and software; there’s no way of competing with their efficiency and affordability. A prime example of good management and control came to me from the way that Davidson Water, a water treatment and distribution company in North Carolina, decided to upgrade its services more than 20 years ago and is still benefiting from the same software today, with another $26-million program already under way to help tomorrow.
Davidson Water serves about 150,000 people, including parts of four counties, and it pumps as much as 20 million gallons a day, connecting 54 remote terminal units seamlessly with its water plant and a separate office. The control software they use, from Micro-Comm, has saved as much as $300,000 at one pump station, several million dollars in all operations. “Micro-Comm helped us develop software to enable us to prefill tanks overnight, during the electrical off-peak hours,” observes Gregg Stabler, general manager for Davidson Water.
Water has been saved, too, thanks to the system’s leak detection capabilities, and that is over and above the initial savings when Micro-Comm reconfigured the control of the system to radio telemetry (from telephone). This utility was a consolidation of five water districts and had previously leased telephone lines from as many as five different providers.
Another practical but most significant savings has come from the fact that Davidson Water has a staff of about 70. That’s about 50% of comparable systems. “Their SCADA system has really helped us to stay lean and mean because we can see what’s going on all the time, rather than having to do site checks,” notes Stabler. “We use the system’s data to make adjustments in the way we operate. We can tie data into a hydraulic model and an engineer can use that to prepare a five-, 10- and two-year forecast. We have a lot of stations and do all kinds of valve controls, and it clicks right along. I don’t think it’s possible to be much better.”
Author's Bio: Paul Hull is a frequent contributor to Forester Media publications.
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