You absolutely need a dehumidifier for your basement, especially if you plan for on using the space for storages, living space, and everything.  Dehumidifiers come in various sizes but it is better if you would use a large dehumidifier because it could take away more heat and moisture in the basement.  Usually, small dehumidifiers generally come with water collection pan and are easy to install.  It’s not that difficult to install but most large dehumidifiers have a drainpipe, consider hiring some professionals to do it for you.  Ideally, if your basement is huge, then you need a bigger dehumidifier, the bigger the space then it’s going to be very humid. Keep in mind that most units wouldn’t function very well below 65 degrees Fahrenheit.  In the areas that are not cold, you do not need to run a dehumidifier.  You’ll just be wasting money, time and energy.  Dehumidifiers are also useful if you decide to heat your basement during cold seasons.  When it gets too hot, you could always use the dehumidifiers.  That is one way of taking out the heat.  Dehumidifiers are very helpful during summers.  Sometimes, it gets really hot in the basement and it’s not very comfortable to spend time in a very humid place.   Again, in areas that seem to be very cold, you don’t need to run the dehumidifiers.  If you do, it will break the coils and damage the unit.  Having a dehumidifier in your basement is an advantage because you wouldn’t have to worry when things get humid in your basement.  Most people buy a dehumidifier because they know that they would have an advantage over it.  One way to know that your dehumidifier is removing moisture is to look at the amount of water in the pan. If it has a lot of water, then it’s removing a lot of moisture.

There are various techniques that can be applied to cope with basement water leakages or moisture. They include:

Drainage sealers – this method is very effective in preventing penetration of water into the basement even in rainy seasons. This completely eliminates any possible occurrence of mould and decay caused by moisture. Sealing can be achieved by use of polymer based compounds. The polymers also prevent wood-eating insects from attacking timbers as well as wood rot. It is important to note that you should apply those sealers that are waterproof only.

Cleanliness of the gutter is also an essential factor that reduces chances of basement water. Debris and other forms of dirt lead to clogging of water. Downspouts should also be positioned several feats from the foundation of the house. A splash block may be placed beneath the rain gutter to disperse water away from the foundation wall. If the area where the house is located is naturally humid and damp, consider installing a dehumidifier. Also avoid keeping windows and doors of the basement open for long. During the construction of the house, external waterproofing should also be competently done.

Waterproofing coatings combined with exterior drainage technique – this is normally applied in areas receiving high rainfall. It prevents entry of water into basements through the walls.
Interior water drainage: this method involves pumping water from the basement. The pumps collect and pump the water out before it enters the basement.
The basement walls and floor can be sealed though this is a temporally measure. You should also monitor wall surfaces and seal small crack that may be appearing before they become big to allow entrance of water.

It is important to establish the possible source of basement water since various methods can be applied depending on the source. For instance, some areas may require little landscaping to divert water while for others, ensuring adequate air circulation will dehumidify the room thus solving the problem.
Basement water proofing is easier and far much cheaper if done when the building is under construction other than repairing.