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drainage area. The Engineer described in detail how rain water gardens work to provide treatment. He suggested that a mailing would be done to property owners to gauge interest in these gardens. Based on the interest, a rain water garden system could be designed. The Engineer pointed out that when I35E was constructed through Little Canada cutting Savage Lake in half, a lot of pavement was added to the area with no treatment. As part of the Unweave the Weave project treatment will be provided, however, there will still be some inlets into Savage Lake. The Engineer reported on the issue of water levels and sedimentation in Savage Lake. He reported that he walked out into the lake at each of the inlets. Sedimentation started 15 to 20 feet into the water. The Engineer estimated total sedimentation levels at somewhere between 40 and 60 cubic yards combined for all the inlets. The Engineer questioned whether this was enough materials to warrant removal, noting that there are established yards around the lake, and these yards would need to be disturbed to bring in the equipment necessary for removal. He also pointed out that the change in the City's snowplowing operations which changed from putting a salt /sand mix on streets during the winter to just salt. The Engineer reported that MN DOT and the County have also changed their use of salt /sand eliminating the sand. The Engineer felt that removal of 500 cubic yards of sediment from the Demont/Jackson wetland, the addition of rain water gardens in the drainage area, and the City's elimination of sand as part of snowplowing operations will improve water quality. He noted that in 2006/07 the City removed 2,200 cubic yards from Sleepy Hollow pond and in 2003 removed 4,000 to 5,000 cubic yards of material from Round Lake. The Engineer felt that the removal of 40 to 60 cubic yards from Savage Lake given the disturbance to yards would not be cost effective. Aichinger reported that corings were done of the sedimentation delta off Lakeshore and Jackson Street. That delta goes out about 50 to 60 feet and is a sand layer. Another coring was done beyond that point and was lake bottom muck. A coring was done on the east side of Savage and that was clay material, probably deposited at the time the freeway project was done. Aichinger reported that Savage Lake is not an impaired lake nor is Gervais Lake. Aichinger noted that Kohlman Lake is impaired as are some others in the Watershed. With regard to responsibility, Aichinger reviewed the history of change in the way that water resources are managed, noting that regulations change about every five years. In the 1970's and 1980's the sole purpose of regulations was to prevent flooding. It was not until after 1988 that water quality was addressed. In the early 1990's the Water Conservation Act was adopted, and in 1995 the Watershed Districted started regulating buffers to wetlands. Cities are now required to develop Storm Water Pollution Prevention Plans (SWPPP). Aichinger noted that Little Canada is no different than any other city, pointing out that these regulations have all come into play after development of both lots and infrastructure. When streets are reconstructed, cities are now looking at addressing the treatment of storm water run -off and systems such as rain water gardens and underground treatment devices have to be retro -fitted into the system. Improvements are being made incrementally. 83