GROUNDWATER SURVEY GUIDE
Thank you for your interest in a Geodivining Survey to locate and assess the best accessible groundwater source for drilling a water supply borehole on your property. This guide provides all the information you need to know about commissioning a Geodivining Survey and what to expect from it. Further information, including case studies and detailed discussion on Geodivining methodology, can be found on our website.
What is groundwater?
Groundwater is fresh water found in saturated zones below the earth’s surface. It is part of the hydrological cycle – the continuous movement of water on, above and below the earth’s surface. Rainwater infiltrates through the soil into bedrock where it may be contained or transmitted by permeable rock or structures known as aquifers. In most cases, the water will discharge naturally to the surface contributing to rivers and wetlands or creating natural springs, where it will eventually return to the ocean to continue the cycle. These aquifers can be utilised by drilling boreholes which, if located accurately, have the potential to produce good sustainable water supplies and sometimes very high yields.
Where are the aquifers?
It is a common misconception that aquifers can be found anywhere, forming large underground rivers and lakes, but, unfortunately, hydrogeology is not quite so simple. Generally, groundwater fills pore spaces and fractures in variably permeable bedrock and in most areas the movement of water through the rock is uneven and gradual. Large volumes of rock are actually dry. However, bedrock is often broken by faults and fracture zones which provide a network of deep conduits by which approximately 90% of groundwater flow is transmitted. Small fractures drain to larger fracture zones and major faults where hydraulic conductivity can be up to 1,000 x more than that of the surrounding rock mass. Pinpointing and drilling at the vertical intersections of these structural aquifers can produce exceptionally high yields, whereas drilling even a few metres away can result in a lower yield or dry borehole. In most areas the geological mapping of these concealed structures is limited which is where Geodivining can help. Accuracy is key.
Why choose Geodivining?
Geodivining International specialises in accurately mapping faults and fracture zones in bedrock for direct intersection by drilling for maximum borehole productivity. Our entirely unique methodology of geological expertise, remote-sensory work and on-site assessment has been designed specifically to detect and assess these mainly vertically oriented water-bearing structures, even when the bedrock is completely covered. Drilling to develop these water sources affords the benefits of:
These are the primary objectives of the Geodivining Survey.
STAGES OF THE GEODIVINING SURVEY
1. Geological Research
Geological mapping provides good background information on what to expect in any area but is seldom detailed enough to determine exactly where to drill. The occurrence of groundwater is very variable depending on the different rock formations through which it flows. Groundwater surveys require detailed assessment of the geology and geomorphology of every site to identify the most prospective area for best water quality and yield potential. Our research also includes the study of present and historical land use to identify potential contamination risks that may affect the quality of the groundwater, and details of existing boreholes and any old mines or quarries in the area to assimilate all relevant information that might affect or guide our pre-assessment of your groundwater development. This assessment informs us of the likely number and depth of boreholes that might be necessary and also gives you an early realistic indication of the likely drilling budget required for your water supply development. In most cases we find that there is sufficient groundwater prospectivity to advise confidently on the progression with the groundwater survey and development.
2. Remote-Sensory Survey
Remote-sensory techniques, unique to Geodivining, utilise a variety of dowsing or divining techniques to map and assess key water-bearing structures concealed in bedrock. Covering all parts of the survey area, we are able to create a comprehensive overview of the highest yielding and best quality groundwater sources that are accessible beneath your land. Using maps and aerial images, the goal-oriented remote-sensory work prioritises drilling targets, that match or exceed your yield requirements, to be confirmed and marked exactly on site. No other geophysical method can provide this much detailed information so efficiently and economically over large areas, and we often discover faults that have never been mapped before that improve the structural interpretation of the mapped geology. Choosing to drill at random or convenient locations often fails to achieve even minimum yield targets, resulting in excessive expenditure drilling multiple boreholes for sometimes poor or unsatisfactory results. In most cases, Geodivining survey methods greatly enhance the prospects of successful exploration, achieving optimum yields, drilling efficiency and economy.
3. Site Survey
As a result of Stages 1 and 2, we are equipped with a complete picture of the best prospects available on the ground when we come to visit you on site. Using field water-divining techniques, target areas identified by the remote-sensory work can be efficiently confirmed and assessed on the ground and exact locations to drill can be marked. Whilst always aiming for the highest possible yield, we must also take these other important factors into consideration when marking locations. The drilling locations must be:
Exact drilling points will be identified and marked on site at the most optimal locations. Casing depths (to secure boreholes through subsoil into bedrock) and the potential productive depth ranges (usually between 30 - 120m in the bedrock) will be estimated for each location, and the potential sustainable yields will also be estimated.
4. Survey Report
Following your site visit the survey findings will be presented to you in our Basic Survey Report including:
If you choose to commission a Full Survey Report this will additionally include:
PROJECT MANAGEMENT & BOREHOLE LOGGING SERVICES
Environmental compliance for many larger projects includes additional survey and reporting obligations along with drilling and testing permits and abstraction licenses from the relevant Environment Agency. Geodivining International provides all additional support services under our Project Management umbrella, working closely with your chosen drilling contractor. Offering an independent and bespoke service, we will guide you from the initial consultation right through to fully compliant completion and licensing of your groundwater development.
For Quotes and Commissions:
Terms & Conditions can be found here.
In the meantime, please don't hesitate to call or email us with any queries you may have.
We look forward to working with you on another successful groundwater development,
Doug Bates, BSc(geol), FGSA, MGA, MIAH, MSEG,
Consulting Exploration Geologist & Professional Diviner for Water, Hydrocarbons and Minerals.
Founder of Geodivining International.