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HomeMy WebLinkAbout~Master - Special Meeting of the Ames City Council 02/18/2014 MINUTES OF THE SPECIAL MEETING OF THE AMES CITY COUNCIL AMES, IOWA FEBRUARY 18, 2014 The Ames City Council met in special session at 7:00 p.m. on the 18th day of February, 2014, in the City Council Chambers in City Hall, 515 Clark Avenue, pursuant to law with Mayor Ann Campbell presiding and the following Council Members present: Gloria Betcher, Amber Corrieri, Tim Gartin, Matthew Goodman, Chris Nelson, and Peter Orazem. Ex officio Member Alexandria Harvey was also present. POST-CONSTRUCTION STORM WATER ORDINANCE: Stormwater Consultant Pat Sauer discussed how stormwater is currently managed in Ames. She provided the definition of stormwater runoff. Rainfall patterns and how water quality is impacted were explained. She said rainfall events have been monitored, and 90% of rainfalls contribute 1.25 inches of rain or less, which are the events that deliver most pollutants to urban streams. Ms. Sauer said design for water quality best management practices should be centered on the Water Quality Volume required to capture and retain the runoff from the smaller storms for a given site. She defined Water Quality Volume as the storage needed to capture and treat the runoff from 90% of the average annual rainfall. The Low Impact Development approach to stormwater management was reviewed. Municipal Engineer Tracy Warner described the relationship of Uniform Sizing Criteria, which ultimately determines the Water Quality Volume. Storm Water Treatment Train was defined by Ms. Sauer as using a combination of practices in series to manage all types of storm events for water quality and flood management. She said Ames’ Ringgenberg Development has some elements of a Storm Water Treatment Train. She stated that Stormwater Quality Management includes: low-impact development, bio-retention cells, bioswales, native landscaping, permeable paving, rain gardens, and soil quality restoration. She also discussed stream buffers, native landscaping, native turf, permeable surfaces, and streambank stabilization. Council Member Gartin asked if the practices being used in the Ringgenberg Development have been measured. Ms. Warner said the Iowa Stormwater Management Manual describes each practice and the benefits of each. Ms. Warner said Ringgenberg homeowners have been very good about establishing the new plants and practices. Mr. Gartin asked if there are any cost benefit analyses for these practices. Ms. Sauer said there is limited information available since this is a relatively new science. Ms. Warner said each practice has its own cost, and in subdivisions there will not be as much concrete pipe installed, but the practices would use more land space. The background leading toward the drafting of the Ames Post-Construction Ordinance was provided by Ms. Warner. It was noted that the Final Draft of the Model Ordinance was completed in 2006. She said once that was received, staff began going through the template as it addressed Ames’ needs. Ms. Warner outlined the public input process that has been followed. Mr. Gartin asked about the feedback received. She said positive comments were received. The current stormwater requirements were reviewed. Ms. Sauer said there are 47 Municipal Separate Storm Sewer Systems (MS4) entities in the State of Iowa. It was noted that Iowa State University (ISU) has its own permit. Ms. Warner said ISU can’t impose ordinances, but they can have policies. Ms. Warner said the City frequently coordinates with ISU. 2 Ms. Warner described Statewide Urban Design and Specifications (SUDAS), which was adopted by the City of Ames for infrastructure improvements. Ms. Warner gave a detailed explanation of the proposed Post-Construction Ordinance. She said the options are to adopt the IDNR Iowa Stormwater Management Manual, which is the recommended approach, or direct staff to create design and specification documents. Council Member Betcher asked about what other communities have done. Ms. Sauer said several have adopted the Manual, and others have adopted SUDAS, which is a similar approach. Ms. Sauer said Low Impact Development standards are also included in the Iowa Stormwater Management Manual. Ms. Betcher asked how often it is updated. Ms. Sauer said in the past it has been reviewed every two years and two practices per year will be updated. Ms. Betcher asked how the document would be updated if staff was directed to create design and specification documents. Ms. Warner said with current staffing it would probably take two years to create a manual, and then updates would come after that. Council Member Nelson asked how maintenance of stormwater practices would be monitored. Ms. Sauer said hydraulic failure would be a sign of failure, as water should percolate or infiltrate within 48 hours. She also said monitoring the health of vegetation is important. Mr. Gartin asked where a stormwater management manual has been adopted. Ms. Warner said east coast and west coast areas have implemented this more than communities in the Midwest. Ms. Campbell said at the last National League of Cities conference it was very impressive what is being done elsewhere. Mr. Gartin asked if there are any down sides to adopting the manual. Ms. Warner said no, that there is much research being done on the practices, and the manual is being amended based on the research. Mr. Gartin said development in the future would include new stormwater requirements, but there are things existing neighborhoods can do. Ms. Warner said there are rebate programs, rain barrels, soil quality restoration grants, and other opportunities for existing neighborhoods to manage stormwater. Ms. Warner described the procedures and requirements of a post-construction stormwater management ordinance and summarized the main changes from the City’s current ordinance. Council Member Goodman arrived at 7:55 p.m. Ms. Warner said it is being recommended that maintenance would be the owner’s responsibility in all development and redevelopment. Discussion ensued regarding the likeliness that owners will maintain the improvements. Council Member Orazem suggested setting aside a small amount over time to have the experts care for these areas. City Manager Steve Schainker said it would be a very big undertaking for the City to maintain the improvements. Mr. Orazem said a slow deterioration of these developments wouldn’t be noticed until it was severe. Mr. Goodman asked how the Northridge Heights amenity is maintained. Ms. Warner said the City has many easements, and through development agreements have established that homeowner associations do short term maintenance and the City does long term maintenance. Mr. Orazem said the stormwater improvements improve the quality of the watershed as a whole so he wonders why they would be the responsibility of only particular developments. Ms. Warner described the College Creek project and said a water quality grant was received. Further discussion ensued regarding maintenance. Ms. Warner reviewed next steps. Ms. Warner told the Council that staff could finalize the 3 ordinance for City Council consideration and if the Council desired, the first reading could be March 4, 2014. The meeting recessed at 8:37 p.m. and reconvened at 8:40 p.m. FLOOD MITIGATION REGULATORY OPTIONS: Assistant City Manager Bob Kindred provided history on a goal of the previous City Council: to mitigate flooding in the community. He said the Flood Mitigation Study was finalized in December with three next steps: to work on physical improvements, work with watershed management authority, and have a workshop to discuss regulatory options. Mr. Kindred said City Planner Charlie Kuester will give a “Floodplain Management 101” and that Water and Pollution Control Director John Dunn was present for questions, as he managed the Flood Mitigation Study that concluded in December. City Planner Charlie Kuester said the current floodplain maps were adopted in 2008. Mr. Kuester reviewed regulatory terms and the regulations in place. Mr. Orazem asked about the 100-year flood that has been routinely exceeded. Ms. Betcher asked if that is under review. Mr. Kuester said it was discussed that the 100 year flood is underestimated. Mr. Dunn said as a result of the Flood Mitigation Study by HDR the flood frequency occurrence was updated. He said it was calculated that discharge increased the flow rate by about 20%. Mr. Kuester described the current floodplain maps. Ms. Betcher asked about College Creek and Worle Creek map updates. Mr. Kuester said some area around Campustown was removed from the floodplain. He said Estates of Natures Crossing becomes narrower, and an area near College Creek was changed as well. A detailed explanation of the City’s regulations for its floodway fringe and floodway was provided. The mitigation approaches used by the City were also described. Mr. Kuester also provided information on floodplain regulations used by the Cities of Cedar Rapids, Cedar Falls, and Iowa City. Planning and Housing Director Kelly Diekmann said the Iowa Flood Center has maps online of each city that help to describe each city’s regulations. Mr. Gartin asked about the restrictions Iowa State University (ISU) has. Mr. Kuester said they would need a Floodplain Development Permit which they could receive from DNR or the City. Mr. Kindred said ISU’s standard is 2 feet over the flood of record. Mr. Kuester said ISU prefers to get permits from the City even though standards are higher because it takes less time for approval. Possible approaches to regulate the City’s floodway fringe and floodway were reviewed by Mr. Kuester, which included restricting new development, increasing performance standards for new development, bringing lower structures into compliance, and revising regulatory maps. Mr. Goodman asked about fill. Mr. Dunn said putting the fill where the flow is would have a large impact. Mr. Gartin asked if there is tension between evacuating the water and slowing the water down. Ms. Sauer said slowing water down is to filter it and clean it. She also said streambank stabilization is important so the streams can safely convey larger storms. She said native vegetation is very effective. Ms. Warner described the Dubuque rain event that brought 15" of water, which tore through pavement in a park, but an area downstream that had native plants weathered the storm much better. Mr. Diekmann explained the current steps and potential future steps to mitigate localized 4 flooding. Mr. Goodman asked if it is possible to require that renters insurance be purchased by properties at risk. City Attorney Judy Parks said she would look into it. Mr. Gartin wondered if the decisions made here will affect other communities. Mr. Goodman said it was stated that near the improvements a large impact will be seen but farther away from the improvements there will be minimal impact. Ms. Warner reviewed current steps being taken to mitigate localized flooding as well as potential future steps to mitigate localized flooding. She said two water quality grants are currently available and the applications will be presented to the Council next week. Mr. Schainker said this presentation on regulatory options is the companion to the capital improvements to mitigate flooding. He said staff has fulfilled the obligation to report back to Council. Mr. Goodman asked if this will come up again if no action is requested. Mr. Schainker said the subject of localized flooding will be discussed again, and the projects will continue. CITY COUNCIL COMMENTS: Mayor Campbell said the issue of residential occupancy went through the House and is being introduced in the Senate. She also said Mr. Kindred has been dealing with a bill that has been approved by the House, which was introduced by Representative Dave Deyoe to make some updates in State law regarding rural water. Mr. Kindred said the bill does not accomplish the City’s greatest goal and has a lot of room for improvement in the future, but makes some improvements to the law. Mr. Gartin said he appreciates the efforts of City employees on snow removal. CLOSED SESSION: Moved by Goodman and seconded by Nelson, to hold a Closed Session as provided by Section 21.5c Code of Iowa, to discuss matters in litigation. Roll Call Vote: 6-0. Motion declared carried unanimously. ADJOURNMENT: The meeting adjourned at 11:27 p.m. ___________________________________ ____________________________________ Diane R. Voss, City Clerk Ann H. Campbell, Mayor ___________________________________ Erin Thompson, Recording Secretary