Tap into underground spring ? - 12/17/06 05:12 PM
Before delving into my first post, I want to thank everyone in the forum for all of the great advice you give - you are a terrific community. I only found your forum a month or so ago & it is a great resource for a beginner like me. On to my Q:
Our 1.5 acre neighborhood lake is fed by a 36" culvert of our city stormwater system which drains about 30 acres. When the water level in the lake rises to a certain elevation, there is a concrete weir at the opposite end of the lake from the culvert so that excess runoff can overflow back into the city stormwater system and eventually discharge in to the Bayou Vermilion. Well after about 20 years of residential development, silt had filled in the upper 1/3 of the lake, so the city drained and dredged out the lake. I haven't cross-sectioned it yet, but the shallow end of the thalweg will be about 7 feet deep and the deep end will be about 11 feet. There is a "shelf" of flat bank about 10-20 feet wide around the lake perimeter that will hold about 1' of water when we get enough rainfall to fill the lake up again - about 5' to go.
Anyway, several of our long-term neighbors swam in the lake as kids, and remember feeling water coming up from the lake bottom, fed by an underground spring. AAMOF, a construction job not far from here had to use matting years ago when digging ditches, because they hit the spring when digging.
Now I am not sure if the spring still exists (do they dry up?) under the lake bottom, or if we should try to tap into it. Also if we drill and hit it, would it feed our lake (potentially good) or would our lake feed the spring (bad)? Also if we were to poke through the clay into sand, we could lose water that way too.
When we have dry summers, the evaporation really drops the water level quickly & I was looking for other water sources for these dry periods. Please offer any suggestions you may have.
Thanks,
Kevin
Our 1.5 acre neighborhood lake is fed by a 36" culvert of our city stormwater system which drains about 30 acres. When the water level in the lake rises to a certain elevation, there is a concrete weir at the opposite end of the lake from the culvert so that excess runoff can overflow back into the city stormwater system and eventually discharge in to the Bayou Vermilion. Well after about 20 years of residential development, silt had filled in the upper 1/3 of the lake, so the city drained and dredged out the lake. I haven't cross-sectioned it yet, but the shallow end of the thalweg will be about 7 feet deep and the deep end will be about 11 feet. There is a "shelf" of flat bank about 10-20 feet wide around the lake perimeter that will hold about 1' of water when we get enough rainfall to fill the lake up again - about 5' to go.
Anyway, several of our long-term neighbors swam in the lake as kids, and remember feeling water coming up from the lake bottom, fed by an underground spring. AAMOF, a construction job not far from here had to use matting years ago when digging ditches, because they hit the spring when digging.
Now I am not sure if the spring still exists (do they dry up?) under the lake bottom, or if we should try to tap into it. Also if we drill and hit it, would it feed our lake (potentially good) or would our lake feed the spring (bad)? Also if we were to poke through the clay into sand, we could lose water that way too.
When we have dry summers, the evaporation really drops the water level quickly & I was looking for other water sources for these dry periods. Please offer any suggestions you may have.
Thanks,
Kevin