After a couple of days of drying time, I resumed work and placed a 10 inch PVC overflow pipe across the dam and quickly covered it. Due to more impending rain in the forecast and the realization that I didn�t have time to mine enough material to finish stacking the new dam to a finished height, I purposely installed the overflow 2 foot lower than I would have liked. After this adventure a backhoe attachment for my tractor is definitely on my wish list. Scraping hard clay with a box blade and front end bucket is literally a pain in the tractor seat.
After installing the pipe I used a previously staged stock pile of white clay to quickly finish lining the large pond side of the new dam, and do some touch-up. As soon as I completed the renovation of the larger pond it began to rain.
(Above) The new dam is almost complete. The white pvc overflow pipe is visible in the left side of photo. (Below) View from the larger dam overlooking the relined pond and the new, smaller pond's dam.
And rain it did. A literal gully washer. It rained two inches in about 30 minutes and I watched in horror as the small pond received the runoff from the meadow. The water rose quickly and soon engulfed the 10 inch overflow pipe, ultimately achieving a height 1 foot above the top of the pipe, inches shy of breeching the unfinished dam before receding . The rain had filled the small pond completely and the larger pond filled up to about a 3 foot depth.
After a few days of drying time I resumed construction and dug an overflow spillway for the new pond. While doing so I used the dirt I removed from the spillway trench to complete the dam. For the next few weeks measurements showed the small pond receding about 1/8 inch per day, and the larger pond dropping about 1/4 inch per day. So far, so good.
