Loading...
PC Minutes CHANHASSEN PLANNING COMMISSION REGULAR MEETING SEPTEMBER 20, 2016 Chairman Aller called the meeting to order at 7:00 p.m. MEMBERS PRESENT: Andrew Aller, John Tietz, Maryam Yusuf, Nancy Madsen, Steve Weick, and Mark Randall MEMBERS ABSENT: Mark Undestad STAFF PRESENT: Kate Aanenson, Community Development Director; Alyson Fauske, Assistant City Engineer; MacKenzie Walters, Planner; and Roger Knutson, City Attorney PUBLIC PRESENT: Lynne Etling 7681 Century Boulevard Elizabeth Kressler 1750 Valley Ridge Trail North Jenn Singer 8470 Pelican Court Shirley McGee 1950 Andrew Court Terry O’Toole 8418 Burlwood Wendy & Craig O’Connor 1702 Valley Ridge Trail North Kim & Dan Obermeyer 1540 Heron Drive Melanie Mertes 8671 Flamingo Drive Tim & Shamus McNeill 1824 Valley Ridge Trail South Jim Wagle 8411 Egret Court Jeff & Kristi Strang 1701 Valley Ridge Trail South Denise Choiniere 8481 Bittern Court Pat Mazural, Bremer Trust 9501 Virginia Avenue South, Bloomington PUBLIC HEARING: 6845 LAKE HARRISON CIRCLE: VARIANCE REQUEST TO BUILD A PAVER PATIO AROUND A POOL AT PROPERTY LOCATED AT 6845 LAKE HARRISON CIRCLE. Aanenson: Commission Chair before we start can we just verify the applicant’s here? I’m not sure if they are here. Aller: The applicants are present. Aanenson: Sorry. We tried to save you a spot up front. I’m sorry, we’ll proceed. Chanhassen Planning Commission – September 20, 2016 Walters: Alright, this is a staff report for planning case 16-22. The 6845 Lake Harrison Circle variance. The applicant has requested a variance to allow a pool area to be constructed in their rear yard. The pool area would involve a 1,500 square foot paver patio with permeable pavers around a proposed 40 by 18 pool. The property is located in the Lake Harrison subdivision. Lot 2, Block 2. It is zoned residential single family. The variances involves several different aspects of the zoning code. The residential single family zoning code has a 25 percent lot coverage maximum. This area is also within Harrison Lake’s 1,000 foot shoreland management district which is a zoning overlay that also has the 25 percent impervious coverage limit. The City also has a blanket provision for all low density residential that limits detached rear accessory structures to a maximum of 30 percent rear lot coverage and there is a Manage 1 wetland to the rear of the property which with the current subdivision has a 20-foot buffer and a 40 foot building setback. A little bit of history on the parcel is currently it has constructed a single family house. It’s zoned for residential single family as I mentioned. All of Lot 2 has a blanket 5-foot front yard setback variance and in 2009 the house had a deck constructed on the back. In 2011 the deck was expanded by another 320 square feet and in 2013 the original homeowner did apply for a pool. The permit was approved but they ended up withdrawing the project. Currently the applicant has applied, the new homeowner has applied for the aforementioned 1,500 square foot paver patio around a pool area. In order to accommodate this, it would require a 1,459 ¼ square foot variance on the lot’s hard cover maximum. That’s an 8.14 percent increase. They would also require a 269 ½ square foot variance on the detached rear yard coverage for an accessory structure. That’d be a 4.5 percent increase and it would also require a 15-foot setback from the wetlands area. The applicant proposes to mitigate the increased hard cover through use of a permeable paver system. This system would be engineered to have 2 ½ feet of ¾ inch clear rock and 1-inch granite chips below. The system would be designed to allow storm water to infiltrate in and would have a release valve for when it exceeded capacity. They are proposing a 2-foot-deep rain garden in the southwest corner of the property and a retaining wall that starts at 5 feet and tapers down to 2 feet as it runs southwest to direct any runoff into the rain garden. They believe that this will significantly improve on the site’s current infiltration and they’re also proposing to place signs to delineate the boundary of the wetland. When staff evaluated this proposal there were several concerns with the proposed mitigation for impervious surface. The Water Resources Coordinator indicated that it is not generally accepted practice from the DNR to allow permeable paver systems to exceed the 25 percent hard cover cap for the shoreland areas. The big reason for that is concerns about their efficacy over time. Essentially like any system as they age their effectiveness decreases. Permeable paver systems require a large amount of maintenance in order to function at optimum capacity. The City does not currently have any provisions in place for monitoring the maintenance or enforcing the maintenance of these structures. With a pervious paver system of this size if as little as 2.7 percent of it became impaired due to dirt clogage, age, other problems it would be the equivalent of allowing over 25 percent with standard hard cover so there’s a very narrow margin of operability. The other concern we have relies around the fact that the hard cover provisions for single family districts are not only concerned with water infiltration. It is also a matter of viewscaping. The reason why the words lot coverage is used is because the main goal is to insure a large amount of green space in our residential neighborhoods. This is also reinforced by 2 Chanhassen Planning Commission – September 20, 2016 the provision which limits detached accessory structures to a maximum of 30 percent real lot coverage. In this case the proposed patio would exceed both the lot coverage limit for the entire lot and the real lots coverage percentage by a substantial margin. We are concerned with the precedent this would set in terms of the ability to cover backyards with extensive patios and alter the fundamental views of the neighborhood. It should also be noted that, the next concern involves the wetland setback. The depiction you see on the screen above you is the current wetland. The purple line indicates the existing 20-foot wetland buffer and the green line shows the current 40-foot setback from that buffer. Under the ordinance that currently governs this parcel no structure is allowed past the green line. If you would switch to the next slide please. The applicant does have the option to use a clause in Chapter 20, Section 411E which allows them to upgrade the buffer to be in line with current zoning standards. This would be in this case a 25-foot buffer with a 15-foot setback. The picture on the right, the green line shows where the adjusted setback would be for accessory structures. The slide on the left by contrast show, the green line indicates the current structure setback. As you can see in both cases the proposed paver patio and pool area encroaches substantially into the existing buffer and that is the reason, I’m sorry existing setback and that is the reason why a 15-foot wetland setback variance would be required to accommodate the proposal. Again it would be possible to design a pool that is in line with the setback requirements as well as in line with the rear yard lot coverage requirements. This is an overview of the Lake Harrison subdivision. When staff looked through the building files for properties throughout it we discovered that a large number of properties were built in a very similar configuration to this house. Approximately 18,000 square foot lots that have lot coverage in excess of 24 percent as-built. In short a decision was made by the developer to build rather large houses on lots that are about average for Chanhassen. This resulted in not many options for increasing impervious surface coverage but it does allow for decks and other things that do not count as impervious surface to be built in the year yards. Going through the files we could find no variances on record for any property within the subdivision excepting the blanket 5-foot front yard setback variance for all houses in Block 2. In summary the house is zoned for residential single family and currently accommodates that use. There are numerous activities that could be done and developed in the back yard within line of code and because of that and concerns with the implication on viewscape, the wetland setback and stormwater infiltration staff recommends the following motion to deny the variance request. If you have any questions, I’d be happy to take them at this time. Aller: Any questions from the commissioners at this point? Weick: Is the pool considered an accessory structure? Walters: The pool is classified as an accessory structure under our ordinance. However, we have by policy not included pools in hard cover calculations so the 1,500 square feet that I mentioned does not include the 40 by 18-foot pool area. Only the paver patio apron around said pool. Weick: Got it, thank you. 3 Chanhassen Planning Commission – September 20, 2016 Walters: Yep. Aller: So from your answer my understanding is that the pool is fine. It’s the pavers around it. Walters: I can say that depending on how designed, as I mentioned in the history in 2013 the original home builder applied for a pool. He was, the permit was approved. My understanding from the records is that there was a deal where he was going to remove some of the impervious surface from the driveway in order to accommodate a small pool apron and then he was going to use I believe decking for the rest of the pool area but it is possible to put a pool in that back yard under the code yes. Aller: Any additional questions at this point? Okay, if the applicant wishes to come forward they can make a presentation at this time. Barb Hegenes: Good evening: I’m Barb Hegenes, 6845 Lake Harrison Circle in Chanhassen. Aller: Good evening and welcome. Barb Hegenes: Pardon? Aller: Good evening and welcome. Barb Hegenes: Oh, you’re not loud enough. My son and I have been kind of a part of the Chanhassen community for the last 15 years and we haven’t lived in Chanhassen but we always wanted to and now he’ll be going to Chanhassen High School. We finally had the opportunity in April to move into the city of Chanhassen. All of our friends and many of our family live here so when we found the house, originally we looked for a house with a pool because this is kind of a big project to undertake but when I bought the house the owner had said that he had already gotten the City’s approval and so it wouldn’t be a big deal to put a pool in so I contacted Mark Hauri with Outdoor Escapes and learned that he had put in several of the pools and done the landscaping in our neighborhood. There’s 3 or 4 other pools in our neighborhood so I didn’t anticipate that it would really be a huge issue to put the pool in as we now know it’s become kind of complicated but Mark and I have been working all summer. Actually since the beginning of May to try to make this happen so I’m going to turn it over to Mark now and let him give you the gritty details. Aller: Great, thank you. Mark Hauri: Thanks for hearing us. My name’s Mark Hauri with Outdoor Escapes so I’m a landscape designer that’s worked with Barb and her team to go through the engineering of this. I’ve also worked with the, had a couple meetings with the Riley-Purgatory Watershed. I showed them the plans. Reviewed it with them and they were actually onboard with what we were doing 4 Chanhassen Planning Commission – September 20, 2016 and made the comment that we wish more people would do things like you do and be forward thinking in this so anyways we want to come before you and you know present what we have. We’d really like to get the pool in for Barb so I do actually have some pictures of the lot I could hand out to people. I don’t know if that helps you at all or. Aller: That’s fine. Mark Hauri: Is that okay? Aller: Yep. Mark Hauri: And so I’ve got pictures and then also kind of a little sketch. There we go. Oh that’s cool. So this is kind of what we’re proposing to do. It’s a little bit dark. Right now, put it back. Right now the lot itself, everything from the front yard, rear corner of the house and everything in back drains right to the watershed that’s in back. Drains directly to it so one of our main focuses was just the ecology of the wetland and instead of having this water just run off the sod right into the wetland we decided that one of the best options, not only for the pool but just to help the ecology of the wetland would actually be to pick this back grade up. Actually build a wall kind of right along this back to alleviate the water runoff that’s coming from the house, that doesn’t have any gutters. From the front yard and from the back that runs right into the wetland so our big thing right now, number one is actually building this wall to actually pick up the grade and that would be on the house side of that setback line. That allows us to flatten out the whole yard and now we can actually do this permeable paver structure. We’ve engineered 2 ½ feet of rock based on the soil tests out there. We could actually go deeper if we want more holding capacity and then our overflow pipe will go to a rain garden on this wet side so really now everything running off, everything coming off the roof, everything off that pool deck will infiltrate in the permeable pavers and any overflow will go into a 2-foot-deep rain garden before anything will come over the wall to the wetland. It’s a really tight lot. I mean as they presented. It’s actually a really difficult lot to work anything in the back yard and I know we’re asking for a little bit more than normal but again I actually had gone to the Purgatory, or Riley-Purgatory Watershed and talked with them about it and they felt comfortable with what we are doing too so that led us to the variance process and here we are today. So if anybody has questions. Aller: Questions at this point. Did you have the calculations on exactly how much water will be held? Mark Hauri: I don’t have true water calculations. What will be held. I mean that’s something we want to do once we excavate down. We’re actually going to do soil bores. We’re going to have 12 soil bores all the way around to determine every point that we’re going to have water in so it will be a little bit easier to calculate at that point because then we can actually calculate correct infiltration rates. Aller: Is there a architectural reason why we can’t put in the pool without the pavers? 5 Chanhassen Planning Commission – September 20, 2016 Mark Hauri: Well the pavers, you know it’s really the deck you know for chairs. Things like that. We could actually put a pool in, in theory. Do some coping around the outside and then sod it. You know we still want to pick the yard up. We still need to flatten out that yard so that wall needs to go in. The pavers, the permeable system will allow more infiltration quicker than the sod will itself. Plus, we’ll have more holding capacity with that top 2 ½ feet of rock. So the pavers do provide, the permeable pavers do provide a better infiltration of that water as opposed to sod. I know one of their concerns was you know if everything clogs up. If there’s a couple percentage points that this won’t drain as well as when it’s new and I understand that. That’s one big question that every city, every government raises about permeable pavers. This is a little bit different because it’s in a back yard environment so we’re not going to be plowing this. It won’t be exposed to salt and sand. The minute the snow hits it, it just stays that way so as opposed to a driveway, a front sidewalk, a street, it’s not going to see the sand. It’s not going to see the salt and that’s the main reason for these to clog up. So my concern about this system clogging up and plugging up over many years is, to me it’s not even a minor concern just because of it being in the back yard and not exposed to any winter salting or sanding. Aller: Is there a reason you’re tied to the size of the pool? Is there a way to restructure the pool size so that you can fall within the maximums that are set out now in the zoning? Mark Hauri: It would be virtually impossible to get a pool in to fit. We have talked about doing a little smaller pool, 36 by 18. We have talked about the potential for changing the angle a little bit of the pool. Maybe taking a little bit more off the back side, kind of that long run right above the boulder wall. You know there’s probably a good 150-160 square that could be taken off there. Changing the angle of the pool a little bit would help. That could take off a couple hundred square but in general with this permeable system you know we might still be looking about 1,200 to 1,300 square feet of the back yard with this permeable system. Aller: Is the permeable system required? Mark Hauri: The permeable system isn’t required but just to be good stewards to the land, what we don’t want to do is put a concrete surface in that has no infiltration and that we just shed water off to the edges and then try to collect it with drain tile and run it into a drain rain garden. A rain garden would just be overwhelmed with the amount of volume. The permeable system allows that water, we can capture that water and have it fill up and actually infiltrate down even after the rain storm so that’s why we went with permeable pavers right off the get go because we wanted to mitigate any runoff that we had. Really let everything soak in and once everything comes down that side hill it’s actually going to be directed right to the pavers so again that runoff can hit our hard surface. The permeable pavers. Get into our drain field and anything that overflows then the rain garden can maybe handle that overflow. But it has a tremendous capacity. I mean it would have to fill up 2 feet to hit that overflow valve and that’s a tremendous capacity so. The permeable pavers we thought about it right away just because we just felt we 6 Chanhassen Planning Commission – September 20, 2016 were being much better stewards to the land going that route than just a straight concrete pool deck. Aller: What’s the capacity of the rain garden itself? If you had a rain garden in there with no pavers. Mark Hauri: If we had a rain garden with no pavers, what we would actually do is we would engineer that rain garden and make it probably about 4 times the size so basically this whole, this whole corner right down here, we would actually create a larger rain garden. Maybe have a 3 foot deep. Maybe actually do some soil correction. Put 3 feet of rock in there. Some sand and then have a 2 ½ - 3-foot depression too so kind of doing the same thing as a permeable pavers but we would have a rock retention area and then the rain garden up above that to just maximize the amount of water we could get into an area that was you know probably 20 by 30ish. Something like that. 20 by 40. Aller: Alright, thank you. Based on my questions anybody have any additional? Tietz: Andrew, yeah. Aller: Commissioner Tietz. Tietz: The excavation for the pool itself. Mark Hauri: Yes. Tietz: You said that you haven’t done any soil bores but you, do you know the consistency of that soil? Is that going to be soil that you can use behind your boulder wall to build up or is it, because it’s getting pretty close to a wetland. Mark Hauri: Yeah we’re actually going to take all that soil off site. Tietz: Off site. Mark Hauri: Yep it actually, we did 4 tests and it actually drains very well. We did 2 kind of what I would consider on the back side of the pool. Between the pool and the wall and we did one kind of where the lounge chairs are and one kind of by the deck and it is pretty good draining soil. We are still going to excavate that soil and actually bring it completely off site and everything that when we build that wall we’re actually going to use granular fill in back of that wall again which is going to be a porous rock. We’re not going to use a Class V or recycled. So really everything from the edge of that pool to the boulder wall will still have a permeable system below it. Above that wall we’re going to do a big hedge of box woods so we will have a planter that’s maybe 3 feet wide by about 2 feet deep of nice black dirt that we’ll be bringing in 7 Chanhassen Planning Commission – September 20, 2016 but everything that we excavate out at that, you know basically it’s about a 3-foot depth, we’ll be bringing that material off site. Tietz: Thank you. Mark Hauri: Yep. Aller: Additional questions? Alright, thank you very much. Mark Hauri: Okay, thank you. Aller: Okay at this point in time I will open the public hearing portion of this item. Anyone present wishing to speak either for or against the item or comment on the application may do so at this time. Seeing no one come forward I’ll close the public hearing and open it up for questions, comments and concerns of the commissioners. Tietz: I think they should be applauded for the work on the permeable pavers and the depth but I think the, you know the amount of surface area that’s encroaching upon the wetland is pretty significant. It’s over 1,400 square feet so to mitigate that I don’t think the permeable pavers really do that and it’s really setting precedent. Aller: Let me ask you a quick question. How is the City and the planning department, how have we dealt with pervious pavers before in the calculations? Walters: Yeah so I’m not kidding when every week I do get a call from builder asking how we deal with permeable pavers. I got one Monday actually. The answer has always been the City of Chanhassen’s policy is we treat them as hard cover. We don’t allow credits and we consider them to be the same as concrete. That’s largely due to the maintenance concerns. I do believe there’s one commercial development that was allowed to use permeable pavers. Kate could probably talk a lot more about the conditions that were placed to make the City comfortable with that but residential has never been allowed. Aller: And I ask the question I’ve never seen it used and even with sport courts I know that we haven’t allowed it so any additional comments or questions? None? Alright, I’ll entertain a motion if anyone has one or would like to bring one. Yusuf: I’ll make it. Aller: Okay. Yusuf: The Chanhassen Board of Appeals and Adjustments denies the variance request to allow hard cover to exceed 25 percent by 8.14 percent, allow a detached accessory structure to exceed 8 Chanhassen Planning Commission – September 20, 2016 the rear lot coverage in the amount of 30 percent by 4.5 percent and allow a 15-foot reduction in the wetland setback and adopts the Findings of Fact and Decision. Aller: Having a motion by Commissioner Yusuf. Do I have a second? Madsen: Second. Aller: Commissioner Madsen seconds the motion. Any further discussion? Yusuf moved, Madsen seconded that the Chanhassen Board of Appeals and Adjustments denies the variance request to allow hard cover to exceed 25 percent by 8.14 percent, allow a detached accessory structure to exceed the rear lot coverage in the amount of 30 percent by 4.5 percent and allow a 15-foot reduction in the wetland setback and adopts the Findings of Fact and Decision. All voted in favor and the motion carried unanimously with a vote of 6 to 0. Aller: So the motion carries. The variance is denied. If you wish to appeal that variance you should do so in writing with the City and the follow up date on that matter before the City Council would again be October 10, 2016. Okay. PUBLIC HEARING: PAISLEY PARK MUSEUM – REQUEST TO REZONE PROPERTY LOCATED AT 7801 AUDUBON ROAD FROM INDUSTRIAL OFFICE PARK (IOP) TO PLANNED UNIT DEVELOPMENT IOP TO FACILITATE THE USE OF THE BUILDING AS A MUSEUM. Aanenson: Thank you Chair, members of the Planning Commission. This request is for a rezoning. There are some other things that go along with the rezoning but the legislative action is to rezone. The property is located at 7801 Audubon Road and the, as stated in the staff report the Bremer Trust is requesting through the special administration or the estate of Prince Roger Nelson to request a use for a museum. The location again is 7801 Audubon Road is located right off of Highway 5 and also access by Audubon Drive or excuse me Audubon Road which is also a collector street. In looking at the request the access again, two streets and that site is 9 acres and the building, existing building footprint is 46,150 square feet and I’ll get in a little bit more detail on that in a minute. So the site is guided office industrial and that’s what we’re, that’s the underlying zoning district that will be going with is also industrial. Everything around this property is industrial and this is taken from our land use map. The property shown with the star on it here, this is the property. The City’s public works is just behind that property and so the request again for the museum is just for this subject site itself and it’s just a rezoning at this time. In looking at the applicant’s request for the site and how they see it being used, there’s no interior remodeling at this time. I know I’ve given you emails and there’s 3 more that I handed out tonight that will become part of the record. There were emails that were attached to that. Similar questions asked about why wasn’t this treated like some other buildings we’ve done in 9