Before you begin Dredging

After you have picked out the dredging area, there are still a few other things that need to be though about before launching and anchoring. One is to make a rough map of the area if it is going to be larger then you are going to need more anchoring.

You can do this on a paper or graph.

The map that you draw out should have possible anchor spots, rocks that need to be cleaned out carefully, or any other thing that you deem important adding on. If you are going to be out there for a good while you will find that drawing out a map and adding in important observations will be of great use.

A map is also a good idea because you can then go marking the areas that have already been worked on and it will also provide you with an estimate of how long you are going to take with the whole area and it then becomes a record that is permanent about your operation. A map will show you areas that have more gold in them and you will then have a reference of what types of places to look into on another trip.

After the dredging area has been checked and finalized there are three more things you want to take into consideration before you starting dredging. These include the point of discharge, the point of intake and the anchor points. In an actual operation these are defined at the same time since the choice of any one is also the choice of the other two. However, each has its own issues and problems.

Usually discharge is decided on first, and of course, as always remember the golden rule: always dredge upstream, never downstream, discharge downstream. As we had previously discussed, little boulder and bigger pieces of gravel inside the tailings have a tendency of depositing really close to the exit discharge of the sluice. Due to the fact that the current of the stream is usually not fast enough to carry them very far they usually start building a little pile that increases in size to the amount of material that was expelled.

If the water is low at the point of discharge this pile of rocks will very quickly increase to reach the bottom of the floats or sluice. When it reaches this point, there are a couple things that can occur. One is that the little hydraulic jump is created that lifts the float or sluice and allows the lower end to move onto the pile of tailings changing the angle and the speed of the sluice.

This can then end up in clogging of the riffle and the gold can be washed down the sluice and forever lost which would be really sad. A little after the sluice jumps to the top of the tailings pile and the pile continues growing more and the discharge and tailings start to build up in the sluice and the pressure box and can cause the suction hose to get overloaded and stop the action and this can occur very rapidly.

Locating a place for the area of intake for the centrifugal pump is always firstly determined by the area of the discharge because the design of the dredge sets the position of the intake hose.

If you are lucky and have been able to find a deep area to discharge the tailings a great number of your intake problems have just flown out the window. The biggest things to consider are: the area should first of all be clear of at least one foot between the strainer and the tallest point of flow sand. In second place, there will always need to be a continual supply of water. In most cases if the sluice is anchored in three or four feet of water intake problems do not come up and most general dredging areas are in this category.