CC_Minutes_2016_0822 - Laserfiche WebLink

Home

Regular City Council Meeting Monday, August 22, 2016 Page 8 question. However, if the City Council prefers not to go as high as 40%, Mr. Lloyd noted any smaller percentage verified suitable by hydrology report stand- ards would suffice. As noted in the RCA, Mayar Roe referenced existing LDR-2 parcels averaging 38% based on a study by Public Works/Engineering staff; and asked how many of those sites were currently in the community. Mr. Lloyd responded that approximately 200 sites were zoned LDR-2, many dis- tributed in small groups, and many as a result of Planned Unit Developments (PUD). However, with the rezoning adoption in 2010, Mr. Lloyd noted that den- sity was rezoned to LDR-2, creating additional lot designations in that category. Councilmember McGehee referenced Section 3(RCE Exhibit B, page 2) a limit of 70% improvement area, including other structures like decks, pergolas, pools, etc. Councilmember McGehee stated she took issue with that, whether or not this language was in the existing code, opining that coverage percentage was too high. Further, Councilmember McGehee stated that, according to her research with the Department of Natural Resources (DNR), they considered decks and/or pergolas impervious versus pervious surfaces, and suggested that city code should do so as well. Councilmember McGehee noted many of those decks and pergolas may sit on heavily compacted soils, concrete or other impervious surfaces, and therefore for all intents and purposes not allowing for any drainage. Mr. L1oyd confirmed that existing city code, while limiting the types of things that may be constructed on a parcel, decks were not considered impervious. Mr. Lloyd noted changes over the years in how city staff addresses structures on a parcel, especially with new technologies for installation and materials; as well as how those structures are initially installed and maintained over time ensuring they remain permeable as intended. Mr. Lloyd noted this ongoing maintenance was addressed via re-inspections and recertification and other means in addressing them as with other best management practices (BMPs). Assistant Public Works Director Jesse Freihammer, advised that ongoing monitor- ing of permeable applications and their design was part of the city's Residential Storm Water Permits (ReSWP) process. Mr. Freihammer noted each system is designed differently, and staff followed and relied on criteria in their specific de- sign specifications that addressed allotted drainage. At the request of Mayor Roe, Mr. Freihammer clarified that when staff calculates permeable surface square footages, calculations were based on performance. Mayor Roe noted if someone was using a permeable surface (e.g, pavers), and not getting up to the limit of 30% or 40%, no analysis was done by staff since the maximum threshold was not reached. Conversely, other pervious portions of the property that were up to the improvement limit of 50% to 70% could be removed