Pond Boss Forums INTRO Questions & Observations SC DNR recommends 6-8ft max depths

So far your understanding of pond design seems good. Ponds at 6-8ft will be weed proliferation zones - constantly resulting in some sort of problem. I assume the SCDNR website recommends fertilizing which if done properly(very difficult) will have phytoplankton shading the water and reducing FA and submerged weeds. Annual fertilzation and maintaining it can be quite tricky. Note that annual fertilization increases rate of eutrophication and hastens the need to rebuild the pond. Average depth and abundant shallow water also have a big part of the frequency of pond rebuilds - clean-outs.

Your pond depth will a lot be determined by location and size-depth of the ravine or valley being dammed. A good builder or dirt engineer will provide insight into this. Remember shallow water (4ft and less) is your big enemy for creating weed problems. Weed problems will be prevalent in all shallow areas if you water is clear 5-8ft(visibility). Clear water tends to be prevalent in areas with acidic or leaches soils. Maybe visit some local ponds. Pond owners love to talk about their pond. Google search your area for pond locations.

If you are going to aerate, then 14-16 ft is an adequate depth - deeper is okay. A good pond builder will better be able to assess maximum depth at the dam. SC DNR assumes no aeration thus 6'-8'.

A Deeper pond than 18ft will require a higher pressure rocking piston pump/s. Also larger ponds need up-sized aeration systems designed to produce adequate turnovers / circulations each day.

State Soil and Water Conservation District may have a list of regional pond builders. Remember a bigger pond goes "bad" (water quality, plankton to sediment) slower but it is a lot harder to fix and more expensive to bring it back to good condition compared to a smaller pond.