Item B: Ordinance Concerning Goal 5 Natural Resources Study

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H. States concern about how top of bank determined, and that the setback could include an existing 45-foot wide flat area plus an additional 40 feet. I. States concern about potential fire hazard and intrusion of transients. J. Asserts that the proposed setback on the Verrijt/Wild parcel would occupy 30% of the lot. A. Staff response (easements): There are a series of28 individual easements along the stream corridor of site E81. These include five sanitary sewer easements, twenty sanitary/storm sewer easements, two public utility easements and one open space easement. More than half the length of the stream channel in site E81 (51 %) is not within any of these easements (l,394 linear feet out of 2,718 linear feet). The easements vary in width. Many of the easements are about 20 feet wide, while several are 7 feet wide. The requirements of the easements along this corridor do not protect the stream channel itself or adjacent riparian vegetation from conflicting uses. Twenty- four of these easements grant access for the construction, maintenance and repair of underground sanitary sewer and stormwater lines. One easement prohibits buildings to maintain open space without granting access. Two grant access to construct, maintain and repair a variety of above and below ground public utilities. One grants a 20 foot wide corridor for storm water flow, and grants access for the construction, maintenance and repair of underground sanitary sewer and stormwater lines. While all of the easements would prohibit construction of structures, none of them restrict other conflicting uses that could damage the resource. No change recommended. B. Staff response (40' vs. 20' setback): In the draft /WR overlay zone, the smallest setback distance is 20 feet, which is applied to primarily to small streams in flat areas. The next level of protection is a 40' setback, which was applied to sites with either higher habitat values or sites that occur in steeper areas. In the ESEE analysis, Site E81 was recommended for a 40 foot setback, rather than a 20 foot setback, based on the steepness of the area. According to GIS calculations conducted by staff, of the total site area of Site E81 (5.8 acres), 4.0 acres (or 69%) has a slope of25% or greater. The channel gradient (the average slope of the channel itself) was calculated by staff to be 11 %. This is based on the stream being 2,795 feet long (0.53 mile), the upper end elevation being 786 feet, and the lower end elevation being 490 feet. Streams with steeper surrounding areas and steeper channel gradients are more susceptible to channel erosion due to the greater velocity at which water moves down the steep slopes, as compared to similarly sized streams in flat areas. For this reason, staff and the Planning Commission have recommended at 40 foot setback for site E81, rather than a 20 foot setback. For comparison, the total area within the proposed conservation area for Site E 81 is approximately 5 acres with an average width of 80 feet. The total area within the proposed conservation area for the Willamette River is more than 468 acres, with an average width of more than 600 feet. C. Staff response (ability of owners to care for the site): Staff does not agree with Mr. Wild that the provisions recommended by the Planning Commission would cause owners to "no longer be able to be responsible for its condition." The proposed regulations allow home owners to maintain existing ornamental gardens within the conservation area without restrictions. Owners would also be allowed to remove hazard trees, remove vegetation that is declared a fire hazard, and remove invasive, non-native plants including English ivy and Armenian blackberries. Owners would be allowed to plant native plants and trees without restriction. Owners would also be able to repair eroded stream banks where such erosion threatens nearby structures. Based upon staffs review of this site and other sites, and the testimony received to date, staff believes these are the activities needed to maintain or improve the condition ofthe stream corridor. D. Staff response (setbacks include buildings): Regarding setback's effect on existing structures, the proposed regulations specifically exempt existing development, such as access driveways,