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Regular Planning CommissionMeeting Minutes – Wednesday, September 2, 2015 Page 6 the most part, water would flow from the site into basins as highlighted in the grading plan 251 displayed by Mr. Lloyd.Mr. Culver noted that site soils were not conducive to infiltration, 252 but did provide filtration through engineered medium or soil several feet in depth in those 253 basins with water seeping through it down to the drain tile and directed in various 254 directions into those highlighted ponds and thereby providing rate control for stormwater 255 on site.Given that situation, Mr. Culver advised that even though there was no direct 256 underground piping in place to a dedicated stormwater system,this drainage plan as 257 proposed should actually reduce the amount of water coming off the site or at a minimum 258 slow it down, creating that rate control directed mostly to the southwest corner of the site, 259 and while this area undulates, it ultimately flows toward an existing catch basin between 260 this site and Marion Street, even though it takes it some time to get there.Mr. Culver 261 advised that staff has surveyed the situation and verified some elevations, indicating that 262 area undulates back there in those naturally graded areas with lots of vegetation, he 263 noted that there would probably be pockets where water still sat due to that undulation. 264 Based on staff’s survey and their personal observations and expertise, Mr. Culver opined 265 that there should be no flooding dangers to any structures, as runoff will arrive at a catch 266 basin before any structure. 267 At the request of Chair Boguszewski, Mr. Culver clarified that the pockets where water 268 could sit existed today and were not created or made worse with this proposal. 269 At the request of Chair Boguszewski, Mr. Culver stated that this project, as currently 270 designed, would not make the current drainage situation any worse, but clarified that 271 during a heavy rain event, these devices would get overrun.However, the way they’re set 272 up, Mr. Culver stated that they will drain over and down, but he could not guarantee there 273 would be no additional drainage to the north of the site because of where future roof 274 drains may be pointed and additional impervious surface being added.Using rain event 275 experienced during the summer of 2015, Mr. Culver opined that with this proposal it 276 would have provided better conditions than currently exist. 277 With agreement from Mr. Culver, Member Murphy clarified that this condition as 278 addressed by Mr. Culver included that for a typical house and additional impervious 279 surfaces. 280 Regarding additional trips for three new homes on this property, Member Murphyasked 281 what the range would be for additional trips generated by residents. 282 Mr. Culver responded that generally speaking for an “average” residential home, trip 283 generation estimated would indicate 9 – 10 trips per day – incoming and outgoing – but 284 would fluctuate depending on the number of vehicles per home and ages of residents 285 and their stage of life. 286 Asan example, Member Murphy noted initial concerns and impressions from residents 287 along County Road B that there would be a dramatic increase, but actually due to the 288 closure of Highway 280, traffic had dramatically decreased. 289 While Acorn Road had its own unique issues, Mr. Culver noted that it currently had a 290 small amount of traffic now, and he foresaw no appreciable increase or negative impact 291 with this proposed development. 292 Chair Boguszewski agreed with that analysis, noting that the development proposal 293 created only an incremental increase of three additional homes. 294 With normal curb cuts, Member Murphy asked how many street parking stalls would be 295 achieved on this private road. 296 Mr. Lloyd provided staff’s estimate of an average of four spaces available on an average 297 driveway with thirteen spaces available on-street; with Member Murphy opining that this 298 seemed more than sufficient for four single-family residential homes. 299 At the request of Chair Boguszewski, Mr. Lloyd suggested the Commission could include 300 an additional condition for Preliminary Plat approval requiring creation of a homeowner’s 301