Center staff presented the major findings of the recently published study Underground Albemarle Revisited: The Role of Groundwater Ecosystem Services in Determining an Optimal Sustainable Population Size for the Charlottesville/Albemarle Community at a March 5 community outreach meeting in Charlottesville.
The purpose of the study is to consider how groundwater management policy impacts optimal sustainable population size (OSPS) in Albemarle County and The City of Charlottesville, Virginia within an ecosystem services framework. The specific research question explored in this paper is – Does groundwater availability impact the determination of an optimal sustainable population size in Albemarle County and the City of Charlottesville and if so, what is that impact? The study embraces a holistic approach to exploring linkages between human population, land use, surface water and groundwater resources.
The Authors conclude with the following Findings:
Findings
1. New language has emerged in recent years to describe responsible stewardship of groundwater resources.
This report introduces and defines the terms:
Sustainable groundwater management
Extractive groundwater services
Non-extractive groundwater services
Sustainable groundwater extraction.
2. Geophysical images reveal that groundwater is not uniformly distributed throughout the study area. In addition, the images specifically reveal the following:
Bedrock fractures are not uniformly distributed, even within the same rock-type on a small parcel of land, and are not always interconnected in a horizontal sense.
Thickness and water storage and transmission capacity of saprolite (the near-surface sponge composed of weather bedrock) vary from place to place, even within the same rock type. In some geologic settings, the only water available for water supply wells exists in the soils and saprolite, above bedrock.
Recharge to water-bearing zones in the saprolite and the bedrock may be very local in settings where both hydraulic gradient and interconnectivity among fractures are low. This means that in some situations, recharge may be affected much more by land cover changes in the immediate vicinity, than by activities that take place farther away.
3. The conceptual foundation of sustainable groundwater management is that demand for non-extractive groundwater services receives priority over fulfilling demands for extractive groundwater services.
The maximum amount of groundwater that can be sustainably pumped from the ground is the volume left over after non-extractive groundwater needs have been satisfied.
4. The County’s previous groundwater studies and groundwater policy have been focused on extractive groundwater services.
The 2003 availability report (ENSAT Corporation and others, 2003) focused on absolute amounts of groundwater that occur in different parts of the county, capable of being “captured” for human use by drilling a well. It should be noted, however, that language in support of non-extractive groundwater services can be found in non-groundwater specific County policy, such as the Introduction to the Natural Resources Chapter of the Comprehensive Plan (Albemarle County, 1999).
5. Stream ecosystem health can be used as a proxy for non-extractive groundwater services, and an indicator for sustainable groundwater management.
The percentage of impervious land cover that is a threshold for onset of degradation ofstream ecosystem health can be used to quantify the percentage of recharge required to supply non-extractive groundwater services. Locally, the degradation threshold appears to be in the range of 5 to 20% impervious land cover. In terms of groundwater recharge, the threshold of degradation to stream ecosystem health can be estimated at diminution of recharge by 5 to 20%. It follows that 80 to 95% of natural recharge is required to fulfill non-extractive groundwater services. This means that 80 to 95% of recharge must be left in the ground, and that amaximum of 5-20% of groundwater recharge in Charlottesville and Albemarle County can be used for extractive groundwater services.
6. The amount of groundwater available on a given parcel to provide for both extractive and non-extractive services varies as a function of hydrogeology, topography and land cover.
There are settings within the study area where groundwater recharge and flow across a given parcel are very large relative to the volume of groundwater needed for non-extractive services. In these settings, it is theoretically possible to sustainably pump significant quantities of water from the ground, and apply this water to a consumptive use where water is transported away from the local watershed. In other areas, groundwater flow and recharge are limited by hydrogeology and other factors. In these areas, the volume of water available for sustainable extraction may be relatively small.
Albemarle County contains two recognizable zones of high potential for significant sustainable groundwater extraction, and one recognizable zone of low potential (Figure 5, above). The remainder of the County and the entire City are within a zone characterized as having mixed potential. Within this area, site-specific study will be required to identify zones of high or low potential, to the extent that such may exist.
7. The use of groundwater for residential needs in the rural area of Albemarle is non-consumptive, in the sense that most of the water is returned to the ground after use via a sanitary drainfield.
Therefore in most cases, under current 2-acre minimum lot size zoning, domestic groundwater use in the rural areas of the county does not degrade non-extractive services, and is generally sustainable, regardless of hydrogeologic setting.
8. Sustainable groundwater management has implications for sustainable population size.
Under sustainable groundwater management, 80-95% of groundwater recharge is left in the ground to provide for non-extractive groundwater services. Simply stated, this means that under sustainable management, over the long-run, the great majority of groundwater is unavailable for extractive consumption by humans. This would seem to imply that the size of the community’s “sustainable” population may be less than-as presumed in previous assessments of water availability-if all available groundwater were to be extracted to supply human needs.
On the other hand, the impact of sustainable management (or lack thereof) could be particularly significant should Albemarle’s EBRF and MRFZ be utilized for groundwater supply. For example, rather than the 3.9 to 7.8 MGD estimated to be available for extractive services from the EBRF under a sustainable groundwater management regime, approximately 39 to 78 MGD could theoretically be pumped, in the short-term, to facilitate commensurate population growth above and beyond what is sustainable relative to protection of non-extractive groundwater services. The results of unsustainable groundwater mining such as this could be widespread lowering of the water table, causing elimination of base flow in many streams and landscape-scale desertification. This has the potential to drastically alter quality of life, and disrupt the local food supply, among other implications for the resident human population.
9. Sustainably managed groundwater could provide a significant proportion of future water needs for the City of Charlottesville and urban areas of the County.
Sustainable groundwater extraction from the Mountain Run Fault Zone (MRFZ) and Eastern Blue Ridge Flank (EBRF) could have a significant impact on maximum sustainable population size for the area. If the County and City were to decide to use groundwater for municipal water supply, a significant portion of the estimated future demand could be supplied via municipal well withdrawals from these two areas.
It should be noted, however, that the County’s longstanding water supply policy is surface-water based. According to Mike Lynn, ACSA Operations Manager, as of August, 2009, the only municipal groundwater system in use by the Authority today is for a small cluster of homes on Red Hill Road.
The following exercise indicates that the EBRF may be capable of supplying from 25 to 49% of the future municipal water demand at build-out:
To estimate the population size at build-out within the County Growth Areas and City combined, we refer to estimates presented in the recent report Estimating Impacts of Population Growth on Ecosystem Services for the Community of Albemarle County and Charlottesville, VA (Jantz and Manual, 2009):
2000 populationBuild-out population
Charlottesville area 72,297 111,882
Crozet 7,101 25,106
Rivanna 3,960 14,205
Route 29 12,458 60,310
TOTAL 95,816 211,503
(difference between 2000 population and estimated build-out population = 115,687 persons)
According to the ACSA, the average water use for all single family residential customers (persons) is 4100 gallons per month or 137 gallons/day, assuming a 30 day month (Mike Lynn, personal communication, 2009). Applying this figure to the future build-out population of 115,687 persons, an additional 15.8 mgd will be needed.
We estimate the approximate availability of groundwater from the EBRF to be 3.9 to 7.8 MGD. This is equivalent to 25 to 49% of the total future demand needed at build-out of the Growth Areas and City, according to the Jantz and Manual projections. Additional groundwater capacity of a similar order of magnitude may be available on a sustainable basis from the Mountain Run Fault Zone, and perhaps from other areas yet to be identified within the mixed zone.
10. This study provides a conceptual framework with which to link residential density, stormwater management, impervious land cover, and non-extractive groundwater services in developing growth management strategies (see Recommendation 1 below).
A $25.00 donation to Conserv: Marketplace for Ecosystem Restoration or to the Center for Sustainable Groundwater or to Advocates for a Sustainable Albemarle Population is requested from those that intend to use the study for professional purposes.
Please contact Michael Collins at 540-661-7379 or Nick Evans at 434-466-1280 for more information.
The Center for Sustainable Groundwater, working with Virginia Groundwater, LLC, and Conserv-Markets for Ecosystem Restoration, is within a few days of release of a new groundwater sustainability report, supported in part by The City of Charlottesville and Albemarle County, Virginia. The report operationalizes groundwater sustainability through methodology to define groundwater non-extractive services and applies the methodology to specific hydrogeologically-defined portions of Albemarle County.
CSG staff and Virginia Groundwater are getting more calls from landowners concerned about groundwater contamination from pesticides and herbicides associated with a wide variety of land uses. This seems to be a result of increased stories in the media about developmental risks to children of certain ages from very low levels of exposure to these types of compounds. It also appears to be the result of cancer appearing in families or their pets and their understanding of the links between contaminants in air, land, and water, and health.
Our unique background in groundwater vulnerability to pesticides and herbicides in parts of Virginia is a helpful background to serve our clients. But, there is way too much we don’t know. What we need is applied research that bridges the use of these products for the purposes they are intended with flora and fauna (including humans) impacts. That holistic science is woefully lacking.
Center staff has recently begun discussions with Susan Leipsner and Van Smith, with Lydia Ministries International located in North Carolina, about ways to improve the sustainability of groundwater development projects in places such as Haiti and Central Africa. For more than a century, developed nations have exported industrialism to foreign lands that lack the social capital to handle it. The results have frequently been disastrous.
Fortunately, many NGOs today, such as Lydia Ministries, realize the need to export not just technology, but holistic programs that include social, economic, and environmental solutions that are specifically place-based and uniquely designed for the culture in which it is being implemented. Van Smith, a former Vietnam helicopter pilot, now drills appropriate technology wells for Equip Ministries, and will work with Susan on a new Kenya water supply project. These particular wells are created using a portable rig that drills a 6″ borehole 100-200′ deep in soft to moderately hard rock. Hand auger and percussion drilling is also used.
A handpump is used to extract the water as shown in the video below:
Both Susan and Van want to provide sustainable water supply solutions. They do a credible job on the environmental front, using geology and geophysical knowledge when they can, assisted by colleagues such as Vincent Allen, with the Consallen Group. Information supplied by Mr. Allen includes:
According to Van, however, supply of a water well, even more than one, is not enough, as described in a recent email:
“A payment for ecosystem services approach”. Yep, that’s a great idea! I was back in the mountain of Haiti last year trying to get water at the top of a 4000′ fractured limestone, vertical strata, mountain. Most of the trees were gone. Very hardworking people! In the dry season they climbed down to 2400′ to get water, often twice a day. I wished one of these grandstanding eco-celebrities would put $10 or $20 million into a tree planting project. Pay 10% of the village workforce to plant trees with 50% payment up front, 25% more if the trees are still alive after 5 years and 25% after 10 years.
Village Level Operational Maintenance (VLOM) has been a buzz-word for some time. It is a VERY difficult concept to get established, even when well thought out and supervised for several years. However, the privately owned simple wells & pumps we’ve done seem to be maintained just fine, even after 5-6 years. The personal investment makes a difference.
We used to repair the deep wells (600′ bore, cylinder set at 140′) installed by the British back in the early 1960′s in Kenya. Sometimes we found pebbles in the top of the cylinder. The herd boys would flick a pebble down the pump spout.to hear it go “DINK, Dink, dink, dink…. We normally charged the village one goat to repair a well. Then we started charging 3 goats if we found pebbled inside the cylinder. The village elders then instituted period of well placed thwacks with a stick on the behinds of any kid caught putting pebbles in a pump and the problem disappeared.
Center staff, working with Virginia Groundwater, and Conserv, would like to find a way to assist Susan and Van with a pilot Payment for Groundwater Ecosystem Services (PES) program in Africa or Haiti. We seek to partner with other NGOs and perhaps university research faculty on a water development/PES initiative.
The report Underground Albemarle Revisited: How do groundwater ecosystem services impact optimal sustainable population size for the Charlottesville/Albemarle community? is nearing completion. The report is being created by Virginia Groundwater, in consultation with Conserv and the Center for Sustainable Groundwater for Advocates for a Sustainable Albemarle Population (ASAP) and their Optimal Sustainable Population Size (OSPS) project. The report will provide an update to the Phase I and Phase II Hydrogeologic Studies completed for Albemarle County nearly a decade ago, through consideration of groundwater from a sustainable management perspective using the conceptual platform of ecosystem services.
The report will provide an example of a sustainable yield estimate from an area of the County estimated to contain significant groundwater yield potential, and link this yield to estimates of build-out provided in another OSPS reports.
The completion of this study is timely. On August 12, Scientific American published a story Is Northwestern India’s Breadbasket Running Out of Water? that describes a lowering of the area’s water table at an approximate rate of 1 foot per year. According to the article, the India government estimates that the area only receives 45 cubic kilometers of recharge, yet is withdrawing 63 cubic kilometers.
The Mission of the Center for Sustainable Groundwater (CSG) is to provide information services to organizations, governments, and landowners for the sustainable development and management of ground water supply. CSG uses earth science, social science, and ecology to characterize community water supply systems through geophysical surveying and groundwater supply planning. The Center is unique in its focus on the intersection of groundwater ecology and hydrology.
CSG is a new sister company of Virginia Groundwater, LLC, a groundwater, geology, and geophysics consulting firm begun in 2002 and located in Charlottesville, Virginia, that specializes in the location of groundwater resources for landowners. The Center is also affiliated with ConservTM, a web-based marketplace for conservation, also located in Charlottesville. The Center designs groundwater programs that enable long-term utilization of well water by our clients, while at the same time safeguarding groundwater ecosystem services, through our experience in hydrogeology and sustainability.
The Center provides site specific and regional scales of management solutions to our clients.
Site Specific Groundwater Management
Our site specific groundwater services are focused on the delivery of a single goal – the greatest yield possible for the longest possible time. Practically, this means the highest possible pumping rate without depletion of water-bearing zones.
To deliver this goal, the Center uses in-house specialized equipment and information, including geologic and soils mapping, air photos, geophysical surveys, land use data, and a variety of borehole analyses, to determine the optimum location and pumping rate for community water supply systems, while maintaining water table and soil moisture for groundwater and food security, a particularly critical issue for groundwater in developing countries and in arid regions of the industrialized world.
Our programs begin with a holistic assessment of existing natural and human systems that comprise the area of need. We then apply science and state-of-the-art technology to investigating groundwater recharge, flow and availability, culminating with selection of optimal sites for water well placement. Our personnel then oversee design and drilling of wells, and develop a management plan that ensures sustainability into the future. The Center’s affiliation with Virginia Groundwater provides applied, market-based knowledge, essential for the implementation of environmentally and economically sustainable drinking water solutions.
Regional Groundwater Management
Our regional groundwater services provide governments and organizations another goal – the sustainable yield of groundwater from a particular hydrogeologic setting or area. The Center defines “sustainable yield” to mean the quantity of water that can be provided for human needs while also leaving adequate supply for ecosystem (natural) services.
The delivery of this goal necessarily involves additional information, including stream morphology and macroinvertebrate data, rainfall data, land cover and impervious surface information, and percolation and aquifer data and mapping. It also is a collaborative process, involving multiple community stakeholders, working together to meet multiple water-related interests.
Increasingly, local, state, and federal governments are seeking to quantify regional sustainable yield to protect groundwater ecology and eliminate groundwater mining.
The Center’s staff has decades of experience in the development of local government policy in the U.S. to sustainably manage groundwater resources. These include source water protection, hydrogeologic investigations, tiered groundwater-based land development policies, groundwater pollution potential mapping, and identification and management of legacy pesticide and herbicide contaminants.
Please contact us
Please do not hesitate to contact us at sustainablegroundwater@gmail.com or call Nick at 434-466-1280 or Mike at 540-661-7379.
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