Trouble In Paradise – EPIC FLASH FLOOD
Today we experienced a thunderstorm which brought with it the most serious flash flood we have seen so far during two years living at the Yankee property.
The water flowing out of the property completely filled the seven-foot precast concrete culvert formed into the new bridge and overflowed the creek banks normal boundaries.
The eight-inch discharge culvert from the upper hillsides and the six new four-inch pipes from the house had trouble keeping up with the volume of water coming down from the sky and down the hill.
At one point our largest catch basin for the 8-inch culvert clogged with debris washed down the hillside. The water then ran down the lawn where the majority was absorbed into the trench drains and smaller catch basins connected to the four-inch pipes.
Without the large basin, the water couldn’t make its way into the smaller pipes fast enough through the trench drains to keep from pooling and forming rivers on the surface. After an aggressive negotiation with a garden spade, the catch basin was back on it’s best behavior.
This flash flood demonstrates the importance of well maintained clean catch basins to allow direct inlet of larger quantities of water faster than can filter through the gravel and filter fabric in a French drain.
This season brought several large storms with volumes of water spread over days and the French drains have performed very well under those slower sustained conditions.
Our perforations in the solid wall outdoor rated four-inch sdr sewer pipe used for the French drain were made with a 5/8 bit spaced with two holes every six inches. After seeing these results I would consider more frequent perforation of the pipe for high flow areas.
Even TWO four-inch pipes (picture right) can only move a limited volume of water in flash flood conditions.
Can you believe contractors who charge over 20 thousand dollars for drainage installations frequently install pipe less than 2 inches in diameter?
A Water Mystery Unfolds
Wait, is that WATER IN THE BASEMENT? After installing 640 feet of new drainage this year? HOW CAN THAT BE POSSIBLE?!?
What could be hiding in this wall?
Is it a pipe?
YEP. That old sheet of paneling ripped out of the old living room is definitely going to hold water! Seriously – when I flipped it over – it was paneling from the old living room.