Types of Wells

Different types of constructed wells

People dig wells to serve as an independent water supply system. These days before a well is dug, a survey is carried out on the site to determine the amount of water beneath the ground, its location, and yielding capacity. This will determine the type of well to be dug.

Types of wells

Generally wells can be categorized into 2 types;

Deep well and shallow well.

Deep well.

From an economical point of view,A well is considered deep when the length of the well is over 25ft or 7.62m deep. What causes the digging or boring of a deep well is as a result of the water table being too far from the top soil. Another reason for a deep well is if although, the water table is not far from the top soil, the soil beneath the water table doesn’t yield water, then the well has to be dug further down to locate the water yielding soil. Types of soil that hold and yield water are those of sand or rock formations. A type of soil that holds water but doesn’t yield it is a soil that consists mostly of shale.

 Another definition of deep well is a well that extends several meters below the water table. Meaning that its source of water is not from the water table but from other water bearing stratum beneath the water table. 

A deep well can extend up to 300m.

Shallow well

A well is considered shallow if the length is less than 25ft from the surface. This is because the water table is not too far from the surface and the soil directly under the water table yields water. 

Shallow wells are also referred to as water table wells. Meaning, the source of water for these types of well is the water table. It also implies that if the water table is further down the earth ( over 25ft), the shallow well extends about the same length or more. Based on the location of water table, shallow wells can be over 35m in extreme cases.

Types of constructed wells

Generally they are of 3 types;

Dug well.

Driven well.

Bored well.

Hand Dug well.

A dug well is done using hand tools. A pick and shovel to dig the shaft, and a bucket and rope to lift out soil. This type of well cannot be dug a few feet below the water table. If the water table is very far from the surface  ( over  10m deep),then a hand dug well may not be economically and practically viable.  Most hand dug wells for private dwellings are less than 10m deep. Hand Dug wells are always shallow wells and they are the least costly.

Driven well

A driven well consists of pipes driven into the ground. The drive point is usually twisted into the ground by hand or powered auger. This type of well is suitable for Sandy soils and cannot be dug through rock formations. The well can be driven up to 100m. It can be shallow or deep,depending on the nature of the soil and water yielding characteristics.

Bored or drilled well

This type of well is also called bore hole. It also consists of pipes much larger than that used in a driven well, bored into the ground using a heavy drilling machine. Bore holes can reach depths of up to 300m and can be drilled through rocky formations. Boreholes can either be shallow or deep, depending on depth of water table and water yielding characteristics of the soil. It is the most expensive of the types mentioned in this article.

The Economics of Reinforced Concrete Slab Design (In-situ)

slab construction

Reinforced concrete slabs can be divided into 2 types. They are In situ and precast slab. Insitu means a slab cast in place. Precast means that the slab is produced somewhere else and then transported to site for installation.

Cast in place slabs are further divided into 3 types. They are solid slab, flat slab and ribbed slab.

Solid slabs refers to slabs supported by beams or walls. They are economical up to spans of 5m

Flat slab refers to  a slab supported by columns only. The main advantage flat slabs have over solid slabs is that they are easier to construct. Also, widows can extend to the underside of a flat slab since it doesn’t require beams for support. The main disadvantage for these types of slab is that they are prone to punching shear. Flat slabs are economical for spans ranging from 5m to 9m.

Ribbed slabs are Slabs in which part of the slab in the tension zone has been omitted thereby reducing its weight considerably. They have higher formwork costs compared to other slab systems.Ribbed slabs are economical for spans ranging from 8m – 12m. 

Troubleshooting Surface or Submersible Water Pumps

submersible water pump & control box

Pump will not start

Possible causes:

Faulty electrical circuit.

Faulty pump.


Check fuses,  capacitor, switches and wiring, control box; replace worn or damaged components.

Have pump repaired or replaced.

Pump will not stop working.

Possible causes:

Faulty pump switch.


Repair or replace switch or control box.

Pump starts but stops often

Possible causes:

Malfunctioning control box, circuit breakers.

Malfunctioning pump/ pump motor.


Repair or replace control box. 

Check for any obstruction to pump motor and remove.

Repair or replace pump motor.

Repair/ replace pump/ pump motor.

Pump is working but no water is being pumped

Possible causes:

Inadequate prime.

Inadequate well capacity.

Blockage at pump intake.


Prime pump.

Switch off pump untill well refills or extend pump intake to a lower level.

Check for any obstruction inside pump or piping.

Pump is working but with excessive noise

Possible causes:

Worn motor bearings of pump.

Faulty pump mount.

Sticking valves in piston pumps.


Repair of replace motor bearings.

Check for any loose pump mount fittings; repair or replace.

Have pump repaired or replaced.

Choosing the right RAM for your PC

installed RAM on PC motherboard

Random Access Memory (RAM) stores memory temporarily for your computer programs to quickly access and use. RAM helps your computer run fast. In Fact apart from the Central Processing Unit, CPU, RAM is the next piece of hardware that helps boost the overall speed of your PC.

Buying good RAM for your PC is as important as the CPU. Even with a good CPU, running your PC on a poor RAM will slow down your PC.

There are many RAMs available, so you must choose the right RAM for your PC. Compatibility is a huge factor, always check that your PC is compatible with the RAM you want to buy before purchasing.


The two major pieces of information you should look out for in a RAM is its speed and storage capacity. The higher the speed and storage capacity of the RAM, the better.

Based on the type of PC you have, want to buy or build, There is usually a maximum limit of the RAM it can take. If you are building a PC, check the information that comes with the motherboard. Compatible RAMs and maximum RAM memory is clearly stated. If you bought a prebuilt PC/ laptop, check its user manual.

Most PCs come with 2 slots for installing RAM. The limiting factor is usually the maximum storage capacity of RAM it can handle. See the figure below. 

RAM memory limits for window based PCs

For instance if a PC can only handle a maximum of 8GB RAM, and it comes with 2 slots (which means you can install 2 RAMs), it’s either you install one 8GB RAM on one of the slots or two 4GB RAMs, one on each of the slots.

It is usually better to install the maximum capacity of RAM that your PC can take on one slot rather than sharing it across 2 slots.Your PC will run much faster using the first option.

How the Vacuum Cleaner Works

Vacuum Cleaner

Vacuum Cleaner s are used to suck up dust, debris and even liquid waste from our houses and environment. Vacuum cleaners come in various shapes and sizes. The bigger they are, the more powerful they can suck up dirt.

How Vacuum Cleaners Work

Vacuum Cleaners consists of 3 major components; 

  • The suction hose
  • The collecting bag or bin
  • The air blowing electric motor.
Vacuum Cleaner showing

The electric motor blows air Inside the vacuum cleaner. This creates a vacuum that then forces the dirt up the suction pipe into a collecting bar or container. The collecting bag or filter is porous, enabling air to pass through. If the air flow through the vacuum cleaner is impeded,it won’t properly suck up dirt. Note that as the dirt collecting bag fills up or the filters become clogged, the suction power of the vacuum cleaner reduces. It is best to empty the collecting bag when it is halfway full.

Troubleshooting your vacuum cleaner.

The most common problem of the vacuum cleaner that people often complain about is that it loses suction power. This problem is easy to fix. Remember that when airflow is impeded, the vacuum cleaner loses suction power. The number of ways airflow can be impeded is as follows;

  • The dirt/dust collecting bag is full
  • The vacuum filters are clogged
  • The suction pipe is blocked

Resolving the issue respectively is to empty the dirt/dust collecting bag, clean or replace the clogged filters , through the suction pipe.

Now, if the above remedies do not solve the problem, then the vacuum cleaner needs to be serviced by a qualified personnel.

How to prepare Potato Salad with Mayonnaise

Potato Salad with Mayonnaise

This type of salad is very easy to make, just boil the potatoes and dress with ingredients.

What you need to make Potatoes Salad with Mayonnaise.

1.5 pounds or 0.7 kg of potatoes.

Salt to taste

Pepper (as you require)

½ cup of finely chopped parsley ( scent leaves)

¼ cup chopped onions

Mayonnaise (to your taste).

How to prepare Potato Salad with Mayonnaise

  1. Peel and wash the potatoes, then put inside a cooking pot, add little salt and boil for about 15 minutes. Make sure not to overcook. After cooking, drain the potatoes, you can use cold water to rinse and drain again.
  2. Put the warm potatoes on a plate and toss it with the chopped parsley,pepper & onions. Next, add mayonnaise, you just add on top of the potatoes or gently mix it with the potatoes.
  3. Serve in its slightly warm state or refrigerate for 4 hours then serve.