More on the Dam
We had several more floods mainly after I arrived back from India. Anyhow it didn’t take much to get run-off as the land was saturated. It did however give us an opportunity to see how well the modifications to the spillway stood up to these overflows. You can see from this photo that the spillway is still in reasonable shape.
This is further evidenced by the clarity of the runoff.
However it still wasn’t quite right. Some wear and tear where the uppermost concreted section hit the gabions at the first drop and also in the intervening region to the second drop. Both these areas were not fully blanketed and some water was creeping around the right wall. (looking at the picture above)
There had also been some subsidence in the blanketed mattress area in the foreground. This meant that the water was not being spread over the entire area.
Solutions: I gave some thought as to how we could improve matters and was looking for simple solutions whereby the changes could be made mostly manually. It didn’t look advisable to take any vehicles into this area as the surrounding ground looked to be still soft.
What Lisa and I did in the end was to collect more rocks that remained in our small quarry at the bottom of this spillway and cover any exposed blanketed areas in the top sections. We also reshaped these sections moving rocks from obviously higher areas to sections that had shown wear and tear when the spillway overflowed.
Then we used the mesh from two spare gabions to re-inforce the levelled first set of gabions. The gabions on the left were from a much earlier attempt at building this spillway and were in bad shape. After we had meshed everything in we then spread another two and half cubic metres over this mesh section to tie it in with the concreted area above.
The pictures probably help you better understand what I have been trying to explain with words. There is still a little work to do on the second section which is the area between these first two gabions and also right at the bottom where the mattresses finish and the overflow rejoins what used to be the old creek bed.
It may look like Lisa did all the work but someone had to take the pictures!