Wolverine Drilling Inc.

View Original

What Is The Difference Between A Good Well And A Poor Well?

What Is The Difference Between A Good Well And A Poor Well?

When trying to determine what may be the best plan of attack for a new well, it is important to know the difference between a good well and a poor well. Some of the top things discussed below will help you understand how to get the best bang for your buck.

WELL DESIGN:

This is a leading contributor to well under performance and well failure. Companies selling 4 inch or 4 1/2 inch will try to convince clients that it is just as good as a 5 inch ID well.

It is not.

A 4 inch pump is designed to fit into a 4 inch well casing, but there is only 1/8 inch clearance between the pump and the well casing wall. This does not account for mineral buildup, debris, deflection of casing or egg shaping of the casing, pebbles or tools that may fall into the well can result in a difficult well service - a 4 1/2 inch casing is still susceptible to these problems.

In 17 years of well construction and well servicing, this has never occurred in a 5 inch ID casing. We have always been able to salvage and repair the well without drilling a new one, to date.

CASING:

The thickness of the casing can be a factor in deflection and egging of the casing. To avoid this, we use the heaviest casing available in Saskatchewan. The casing itself is telescopic and belled. It is solvent welded and seals 100% and will not pull apart once cured. It prevents contamination from outside of the well to the inside of the well. Some methods of coupling casing is to use a threaded casing. The threading removes half the material on the male and female surfaces and becomes a weak spot. We have encountered well that needed repair that was damaged by ground heaving in winter that pulled the threads apart, causing debris to fall into the well. Those wells were 4 1/2 inch in diameter, thus, inside the diameter was too small to re-sleeve and a new well was required.

SCREENS:

Screens and sand filter pack (common name is gravel pack, yet is not used). We use silica sand which is void of contamination and minerals. It will not add anything to the water in the aquifer. It is considered neutral material. When properly placed around the screened area it keeps find sand and silts from migrating into the screened area, it is properly sized for the screen. We prefer 1 to 2 inches thick. If it is too thick the well performance can be hindered or underperform. Too coarse or too thin can create uneven flow in the aquifer and cause silt you migrate into the area of mineralization caused by turbulent flow.

SCREEN SELECTION:

PVC screens are commonly referred to as slotted casing. PVC screens work great for observation wells, sand points. The slotted casing is easily damaged, it clogs easily with debris and is difficulty to clean and wash as the cut in the casing is uniform in size and should only be used in shallow wells unless it is used as a sleeve in an inter-shale aquifer ( not applicable for most Saskatchewan wells ). Once in a while, the need to replace PVC screens does arise but is relatively rare. Slotted casing usually comes in only 2 slot sizes ( 10 and 20 thousandths ).

Stainless Steel Screens are durable, come in a variety of diameters and slot sizes. Slot sizes are the gap between the triangle wire mesh where the water comes in. The larger diameter screens allow for greater surface area for water to enter the well. The less velocity water that enters the screened area of the well - the less opportunity for turbulence in the aquifer to occur which reduces sand and silt migration, reduced mineralization and build up in the screen, hampering well performance.

Done correctly, a well will have a long life and with less maintenance.

The design of stainless steel screens are in such a way that they plug less and are easier to clean. Depending on the depth of well, screen diameter must be considered because it may have more pressure on the screen. Example: 3-inch diameter screens can be installed at greater depths than 5-inch stainless steel. This comes into play at wells that are 700 ft. and deeper. Most domestic/ residential wells do not exceed this 700 ft., but not all cases.

When investing in a water well - it is best to spend money where it counts. Wolverine Drilling Inc. is dedicated to working with you throughout the drilling process to ensure clear and concise measures are taken for both long term well sustainability and overall investment costs.  

Please contact us directly at 306-682-4647 to discuss your options and the best process to follow for the construction of your water well.