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Cliff- visited the Gopher Electronics site yesterday and met with John Reinke, the CEO, and Wes Murname, in charge of the grounds. I made some rough observations and they helped me understand how the roof drainage works. They have a total of 1.6 acres of impervious, 1.1 of that discharging out the back of the parking lot into the eroded area. (see attached map) The silted -.n pond is definitely undersized for the drainage area, and restoring and then maintaining that pond is probably not a feasible option. The primary problem seems to be the erosion that is happening in. the channel that has formed to bypass the pipe, bringing sediment into Savage Lake. Thinking about the site, I see a couple options, perhaps you and Brad have some other ones I haven't thought of. 1. The concrete `chute" from the back of the parking lot seems to be working, but there needs to be some energy dissipation at the downstream end. Perhaps the pond could be somewhat reshaped into a riprapped stilling basin. From there, the water could either be piped into the lake using their pipe, or a new one. Alternatively, a channel could be formed from the basin to the lake, hopefully we could avoid rip.rap and use some sort of mat and vegetation to the water's edge. 2. A drop structure could be placed at the back edge of the parking lot, similar to the drop structure at Snake Creek, and the structure could incorporate a sump for WQ benefit, but my sense is that would be too expensive. 3. The pond could be reexcavated. Again, access for construction and maintenance will be really difficult, and it would still be really undersized. This doesn't seem like a realistic option to me. I'd lean towards Option 1 as it seems to be the least expensive and would stab.i.l.i.ze the eroding area. To promote water quality, their lot seems to be a very suitable candidate for island rainwater gardens. John mentioned that they are hoping to overhaul their parking lot soon, and that seems like a perfect chance to reshape the lot to promote infiltration in island gardens. They already have some very large vegetated islands, but unless the grades in the parking lot are changed to encourage the water to flow towards them, retrofitting may not have much benefit. This might be an opportunity to piggy back on their own resurfacing project and promote infiltration. They care about the.ir grounds and maintain them very well. Both John and Wes have backgrounds in the natural sciences, so they understand the importance of "restoring native hydrology ". We had a very fun conversation about base flow, groundwater recharge, etc. How would you like us to proceed? 2