Case study - View Hill irrigation well

How Well Water 3D helped find the depth and quantity of ground water for a new well

We were approached by a farmer who required a new well in an area where numerous dry wells had previously been drilled. The producing wells exhibited a significant range, with some yielding just a few gallons per second and others reaching up to 20 gallons per second

Red wells are dry, blue are producing water

How deep to drill?

Some wells in the region weren't drilled deep enough because they were abandoned too soon, whereas a 3D model would have clearly shown that aquifers were present just at greater depths. On the other hand, some wells were drilled too deep in areas unlikely to yield water. Both scenarios incurred significant costs.

The successfully producing wells were drilled to various depths, with some having multiple screens indicating they tapped into more than one aquifer.

This pattern is typical of most aquifer systems, where multiple aquifers exist, and they are patchy due to the deposition of porous gravels

A cross section view of boreholes in the region

The 3D aquifer model

After utilizing the available well data in the region to construct a 3D model of the local aquifers, it became evident that there were three distinct aquifers. The lower aquifers, being larger, exhibited higher water production.

All the aquifers sloped from northwest to southeast, indicating that farmers in the southeastern part of the region had to drill deeper to access water. Although the aquifers were not continuous across the region, the lower aquifers generally displayed greater continuity.

Cross-section through the area where the owners intended to drill a new well. Red areas indicate higher water content, while blue areas suggest lower water content. Grey zones represent non-water-bearing sediments, and black denotes bedrock.

Using the model, we can effortlessly generate cross-sections slicing through the earth, illustrating the aquifer geometry and the potential yield of each aquifer. The section above depicts the proposed drilling location and the closest existing wells in the surrounding area.

Understand the aquifer

The patchy aquifer continuity across the region is most apparent in the uppermost aquifer. In the image below, we observe aquifer 1 from a top-down perspective, it becomes evident that it's not continuous throughout the region.

Looking down on the extent of aquifer 1 (the shallowest aquifer). Yellow areas have more water than blue areas.

The region also features non-water-bearing bedrock emerging at the surface in certain areas (indicated in black below). The presence of bedrock disrupts the flow of groundwater from the source. In locations where a fault brings the bedrock to the surface, there's a significant reduction in groundwater, particularly in the southeast of the region.

Bedrock shown in black, grey zones are non water bearing sediments. Yellow areas have more water than blue areas.

Results

The farmer ultimately opted for a shallower well, positioned nearer to an existing power source, and successfully discovered water at the depth identified in the 3D model. The well yielded 5 gallons per second. The flexibility to adjust the well location highlights the significant value of having a 3D model covering the entire site.

The drill log from the successful well