My apricot tree seem to be so weak. And had dead branch ends which I cut off. I have other apricot trees around this tree that drink almost same amount of water and are healthy. But two of my trees that are near this tree are pretty much look the same. Nearby walnut trees and water pushing sand under trees are two things that I thought worth mentioning ad possible suspect What is the problem?
If we go by pictures 3 and 4 numbered from the top, we see an example shoot. What we expect to see in a healthy tree is a number of growth segments (in the pictures we can see about 4 of these with different colour bark on the twig). Each segment represents a year of growth, and each should be about the same length which in a vigorous tree could be 10 cm and the terminal segment should be a bright green. Take a look at one of your healthy trees, choose a twig and make the comparison to this one and you should see quite a difference.
What we see in the non-healthy tree is reasonably normal growth about 4 years ago, followed by progressively poor development each year. Two possibilities, either the tree expanded roots into good soil to begin with and then ran into inert material or the roots are capturing nourishment but it is not getting to the branch tips.
If the land is low at that point and the incoming water causes the water table to rise you need to know how much and what the quality of the water is. If it contains salt you are in trouble since this will interfere with the roots. High water table, even with clean water, can be very damaging to peaches and apricots and is most likely the issue. Punch a metal tube into the ground alongside the affected tree and use it to gauge and monitor the height of the water table through the season.
You might also examine the bark for damage that is preventing the flow of sap to the twigs; however this is unlikely since it would be affecting other trees as well.