Water sampling is one of the most significant sampling techniques applied for different geological, environmental and oil geology projects.
According to the significance of this environment in different projects, water sampling techniques which are applied are of great importance. Two items should be considered are:
Water sampling methods
In this section, the most significant and effective methods are applied for water sampling are completely introduced. For each method, a full description of method and geological application has been offered.
Water Sampling Instruments
Instruments which are applied for water sampling are different from those applied for rock, soil and sediment sampling such as auger, sampling drills. Note that, in this section, just those instruments applied for water sampling are completely described.   

Establishing Sampling Goals:
Probably one the first and most helpful techniques for maximizing the collection of accurate and useful data is to begin with a careful and thoughtful consideration of the goals of the project.
- Provide a perspective on the range of eutrophication conditions found
- Describe water quality conditions in individual lakes
- Provide data useful in developing regional empirical eutrophication models
- Detect trends of deteriorating water quality caused by nutrient pollution.

Sampling Location:
The location of the sampling point in a monitoring program is heavily dependent on the goals of the program. In the past, many limnologists would sample natural lakes at a single site over the deepest part of the lake. There is a good reason for using the point over the deepest part of the lake; it allows the sampling of every possible depth. However, using this point as the single site to characterize a lake assumes that there are no horizontal gradients in the lake; each depth at that single sampling site represents the conditions at that depth throughout the lake. the use of this sampling site also ignores the characterization and influence of the littoral zone, which can constitute a significant percentage of the total lake area and volume.
When sampling water, it is important that the samples that you take for testing are representative of the water system as a whole.