Irrigation channels facilitate the transportation of water from the catchment place to the croplands and orchards which will be watered. It is about works that require an important infrastructure and cost. Either it is about large or small channels, the maintenance is essential so that they can be used during many years.
However, with the pass of the time and the consequences of all kind of weather conditions, as well as the action of some animal species, which constitutes their refuges in soil ditches, and that can produce damage. Also the presence of seaweeds can produce the obstruction of pipes, what supposes reduction of the flow of the pipe and deterioration in the working of the outlets.
What is the solution for this problem?
The pipes of the thermoplastics are an excellent solution for this type of problems and besides it is estimated that they can allow the saving of about a 30% of the water which was used before.
An effective solution for the rehabilitation of irrigation channels is to introduce the new pipes within the ditches, as it were a fitting. In this case, we talk about pipeline networks in load.
To take the flow that is needed in each section it is enough with a level of the free sheet in the head of the outlet and the slope along the ditch. This doesn’t need to be exclusively descending. With this procedure, the available load will be minimum in some sections.
The main advantage that this procedure offers is that it is avoided, almost completely, the levelling of the pipe routing, something that can take time, be expensive and result tedious, like every soil movement operation. When taking advantage of the gravitational energy available in the head, the pipes don’t need to have large diameters and neither it is necessary the use of shields.
From the economical point of view it is a very interesting investment, as the new pipe is introduced within the previous one and it is not necessary to demolish the present ditches. So in this way, the steps are also reduced, it is not necessary so many workers to do the works, and the working time is also shorten.
Another alternative are the free sheet pipes, although in this case it is necessary a soil movement which extends the time period of the work, as the sections of the pipe will be higher than in the load pipes.
The thermoplastic materials that can offer us the best guarantees are the polypropylene (PP), the polyvinyl chloride (PVC) and the high density polyethylene (PE). They will be useful and there are three reasons:
- They are easy to handle to work with them.
- Its cost is lower than the price of the pressure pipes.
- They are thermoplastics which support strong external loads.
The depth of the pipes must not surpass the 85% of the internal diameter to guarantee that it can support the load.
Generally, we can say that to rehabilitate irrigation channels to pipe the ditches is a good solution. The PE, PVC-O and unplasticized pipes (PVC-U), as well as the PE, PP or PVC corrugated pipes improve noticeably the efficiencies at the moment of watering.