As a germophobic, I almost consume a soap bar each day due to the touch of a door handle or other daily used items around the house. This is instigated due to OCD perhaps.
This is unhealthy and bad for the skin (As using too much is harmful and thus there needs to be some control over the issue. One proposed by someone was that just washing the hands by water and not consuming the soap.
Would washing hands with only water be equally effective in most common cases?
Washing your hands with plain water of a normal temperature is significantly less able to effectively sanitise against bacteria, viruses, and many protozoa. The oil on your skin will hold pathogens pretty effectively. The detergent in the soap helps to break down the cell walls in some types of prokaryotes (bacteria) and eukaryotes (other living microbes) and also to remove the oil so that virus particles can be removed in sufficient numbers. Different soaps and detergents will have varying levels of effectiveness. The CDC provides quite a bit of information about sanitisation. This page explains how to wash your hands effectively to remove pathogens.
Here is a quote from a study specifically comparing hand washing with and without soap:
Handwashing with water alone reduced the presence of bacteria to 23% ... Handwashing with plain soap and water reduced the presence of bacteria to 8% ... The effect did not appear to depend on the bacteria species (PubMed 21318017).
The above results may or may not be similar to those for viruses or protozoa. Also, the amount and type of oil on the skin before washing probably plays a large role, as probably does the method and material used to dry the skin. Different situations call for different approaches and levels of sanitation.
Interestingly, the same study mentioned that no specific instructions were given for the washing technique, other than using a paper towel to dry:
Participants assigned to handwashing were asked to wash their hands as they would normally do, without instructions on length of time or thoroughness. The volunteers allocated to handwashing were then provided with a paper towel to dry their hands ... Participants took on average 12 seconds to wash their hands with water alone, and 14 seconds to wash their hands with water and soap (PMC3037063).
Washing your hands with plain water does reduce germs.
It just does not remove as many of them as using soap would.
Source: Same link as Michael, and sorry for the hijack -- I know this to be true from University (where I studied Biology), but could not have come up with an English language source ad-hoc.
Handwashing with water alone reduced the presence of bacteria to 23% (p < 0.001). Handwashing with plain soap and water reduced the presence of bacteria to 8% (comparison of both handwashing arms: p < 0.001).
So, if...
washing with water alone after touching the latter allows you to
...then by all means do wash with water alone if there is no rational reason to strive for more sterility.
That being said, and to avoid being misunderstood, after handling the former group of objects (toilet, pets, trash, ...) or before handling food, everybody should wash hands with soap, obviously.
If one would move his hands while washing hands with raw water, would that help in getting rid of bacteria and germs?
Yes. In fact it can reduce the bacteria on your hands by 77%. This is a significant decrease in bacteria and other contaminants. The primary action responsible for this is the mechanical scrubbing, along with the flowing water to carry away loosened dirt and contaminants.
If so, then why need for a soap?
Soap improves the action of hand washing. Soap and water together with the mechanical action of rubbing reduce the bacteria by 92%.
So soap adds an additional 15% improvement over hand washing with water alone.
Handwashing with water alone reduced the presence of bacteria to 23%. Handwashing with plain soap and water reduced the presence of bacteria to 8%. (source)
