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2003-06-23 EC Agenda PacketAGENDA GOLDEN VALLEY ENVIRONMENTAL COMMISSION Regular Meeting Golden Valley City Hall, 7800 Golden Valley Road Council Conference Room Monday, June 23, 2003 7:00 P.M. I. Approval of Minutes — May 19, 2003 II. Program/Project Updates — ➢ Natural Resources Inventory ➢ NPDES Phase II ➢ BCWMC Second Generation Plan ➢ Boone Avenue & Trunk Highway 55 Project ➢ Bassett Creek Park Pond Wirth Beach Proposed Developments III. Commission Member Council Reports IV. Other Business V. Adjourn GAEnvironmental Commission\Agendas\062303.doc GOLDEN VALLEY ENVIRONMENTAL COMMISSION Regular Meeting Minutes May 19, 2003 Present: Richard Baker, John Giese, Alan Kuentz, Sara Peterson, Joel Wessman City Staff: Jeff Oliver, City Engineer, Al Lundstrom, Environmental Coordinator, Tracy Pharr, Administrative Assistant Absent: Sue Hess, Dawn Hill I. Call to Order Kuentz called the meeting to order at 7:10 pm. II. Approval of Minutes — April 28, 2003 No changes. MOVED by Peterson, seconded by Wessman, and the motion carried unanimously to approve the minutes of the April 28, 2003 meeting as submitted. III. Program/Project Updates Natural Resources Inventory— Lundstrom stated that, at the last meeting, the Commission asked the City to have Short Elliott Hendrickson, Inc. (SEH) come up with a list of other communities that have had natural resources inventories, and what things these cities have utilized them for. Lundstrom distributed a handout of this information. Peterson asked if this would be on the City's website. Lundstrom responded there would be a meeting with the Communications Coordinator, the MIS Coordinator and management to decide what would be best to display on the website so as not to overwhelm people with too much non-essential information. Lundstrom stated he would try to get copies of the Inventory for all Commission Members by the next meeting. NPDES Phase 11 — Lundstrom said that the Communications Coordinator will have the complete version of the Storm Water Pollution Prevention Plan (SWPP) on the City's website by the June meeting. He stated that the Minnesota Pollution Control Agency (MPCA) had acknowledged receipt of Golden Valley's plan. Lundstrom continued that software had been purchased to track the City's implantation of the plan. This software can also be used for Golden Valley's annual reporting to the MPCA. BCWMC Second Generation Plan — Oliver stated that the Bassett Creek Water Management Commission is still in discussions with the Cities of Golden Valley and Plymouth about funding of the plan. Immediately after Tuesday's City Council meeting, the Council will be discussing options such as ad valorem tax, current funding mechanisms, etc. This is an ongoing debate. No focus on the CIP yet. Boone Avenue & Trunk Highway 55 Project — Oliver stated that preliminary design for this project is underway. He noted that there would be a court hearing this week for property acquisition of 710 Boone Avenue. The City is moving forward with a floodplain and wetland water resources study. Golden Valley has met with the Corps of Engineers, General Mills and people at Brookview. WSB & Associates, Inc., the City's consultant, will attend a future Commission meeting (possibly July) to report on the project. Baker arrived at 7:25 pm. Kuentz turned over chairing the meeting to Baker. Bassett Creek Park Pond — Lundstrom said that the Minnesota Department of Transportation (MnDOT) meeting will be held in two weeks. He stated that, in setting up the meeting, MnDOT had already commented this could be a good project for them to contribute to. Lundstrom continued that the neighborhood meeting for this project may be held before the Environmental Commission meeting in June. Lundstrom to contact Hill with this date. Wirth Beach — Not much progress on this project. Lundstrom said that the City of Minneapolis Park Board had asked for a temporary wetland exemption. This exemption would be for construction of a storm water pond so as to perform some quick improvements to get the project going. Longer term, a larger storm water pond or rain garden would be installed. This project should not be confused with the Wirth Lake Trail. Lundstrom stated that he noticed last week upon inspection that the trail had not yet been addressed. Kuentz said that it had been filled, but is still leaking underneath the trail. Proposed Developments — Oliver noted two developments; the General Motors Training Facility, at the northeast quadrant of TH 55 and TH 100, and Calvary Lutheran Church. A company has proposed remodeling the building at the Training Facility for used car sales. No Public Works comments on this project. The City Council will decide on this development's approval at its next meeting. Public Works met last week with Calvary Lutheran Church. The church is in the process of planning for an addition, changes with their daycare facility and parking issues. Kuentz asked what the sequence of events is now for this development. Oliver responded that no plans had been submitted yet, so plan submission would be the next step. After submission, the City has 10 days to determine if the application is complete, then 60 days for approval, which can be extended another 30 days. If the Council does not operate within that timeframe, the development is automatically approved. III. Review Commission Appointment Status Baker requested the attached Commission appointment status for information on election of officers. MOVED by Kuentz, seconded by Peterson, and the motion carried unanimously to elect Richard Baker as chair of the Environmental Commission for the next year. IV. Other Business Items of Other Business: ➢ Baker asked to have Commission Members' reports on City Council meetings as a regular agenda topic. He then asked if anyone had attended a Council meeting since the last Commission meeting. Wessman attended the May 6 Council meeting. He said that the meeting discussed whether a third garage stall could be considered a necessity. Wessman also stated the Council has some concerns on frequent absences of Commission Members at meetings, lack of quorum and whether staff time is being wasted in the event of low attendance. ➢ Baker inquired about upcoming City Council meeting attendance. He commented that Hill was to attend the May 20 meeting. Pharr indicated that she had sent an e-mail to Baker that Hill had called and stated she would be unable to attend this meeting. Baker asked if someone else could attend in Hill's place if there are agenda items applicable to the Environmental Commission. Kuentz to attend the May 20 meeting. Peterson to attend the June 16 meeting. Baker asked how many of the Manager's budget cut recommendations had been implemented. Lundstrom noted staff layoffs and postponement of various building repairs and remodeling. ➢ Kuentz referred back to the Council's concern about staff time at meetings. He noted that three staff members attend the Environmental Commission meetings, and asked if this was standard of other Commissions. Oliver responded that he and Lundstrom are salaried, so only one staff member receives overtime. Baker asked for a recap of the update on the Natural Resources Inventory and NPDES Phase II. Lundstrom reviewed this for him. Giese asked the status of the proposed Wastewater Treatment Plant shared by Golden Valley, New Hope and Crystal. Oliver responded that all possibilities are being reviewed. Baker asked if Clancy could come to a future Commission meeting to discuss the pros and cons of the Plant. Oliver to inquire of Clancy. No additional business was addressed. V. Adiourn The next scheduled meeting will be on June 23, 2003 at 7:00 p.m. The meeting was adjourned at 8:03 p.m. Respectfully submitted, XX��,A � ?LAt4 Tracy E. Pharr Administrative Assistant Department of Public Works =SEN MEMORANDUM 3535 Vadnais Center Drive, St. Paul, MN 55110-5196 651.490.2000 800.325.2055 651.490.2150 FAX TO: Al Lundstrom, Environmental Coordinator - City of Golden Valley FROM: Brad Kovach, Senior Biologist - SEH DATE: May 1, 2003 RE: Natural Resource Inventories, Subsequent Actions SEH No. AGOLDV0209.00 The following is a summary of some of the actions or ordinances that were developed after completion of a natural resources inventory by SEH. Additional recommended actions are also included: City of St Cloud Natural Resources Inventory, 2000 to 2001 SEH conducted an inventory throughout St. Cloud's surrounding partially or undeveloped areas. The City and/or related governing units established the following actions as a result. • The inventory mapped all of the wetlands. The City then passed a wetland buffer setback ordinance requiring a setback for all development that is adjacent or proximal to wetlands. • The City designated several high quality wetlands for "high priority protection" and avoidance. • The City also selected several green space areas identified in the inventory as future parks, or set -asides for conservation purposes. • The results of the inventory were incorporated into the comprehensive planning process. • Restorable wetlands were identified and the City designated these as potential mitigation sites for future mitigation needs. City of Burnsville Natural Resources Inventory, 2000 to 2001 SEH conducted a citywide natural resources inventory and management plan • The City followed with a deer control and management plan that referenced areas identified in the inventory • The City also used the results to plan and develop a new park within a large green space • The City restored a wetland fen that was identified by the inventory • The City utilizes the inventory to identify stormwater management needs and locations for ponding • The inventory is a reference source for identification of sites for a pilot project on rainwater gardens • The City is considering a open space ordinance and water quality monitoring programs that will refer to and utilize results of the inventory Short Elliott Hendrickson Inc. Your Trusted Resource Equal Opportunity Employer Natural Resource Inventories, Subsequent Actions May 2, 2003 Page 2 Met Council/Dakota County Natural Resources Inventory of Elko -New Market Townships; SEH completed a MLCCS Inventory for a proposed utility interceptor project, 2002 • Inventory was utilized to identify sensitive resources to avoid during implementation of project • The Inventory also provided the County with a completed MLCCS for future planning purposes City of Hugo MLCCS; Not completed yet, on hold • The City is primarily interested in establishing a wetland setback and buffer ordinance, and also is interested in nuisance vegetation management Other actions that can result from a natural resources inventory • Surface water management plan and related ordinances • Nuisance vegetation management plan and ordinances • Wetland management plan and ordinances • Wildlife management plans (i.e. deer and goose control plans) • Tree ordinances • Park and recreation area planning • Lake or stream management plans • Ecological restoration (i.e. prairie restoration, oak savanna restoration) • A natural resources management plan • Maintenance plans • Beautification projects • Planning and zoning, including natural resources based ordinances that link to planning/zoning actions • Redevelopment projects that include green space • Biotic community connectivity and corridor planning x:\f\goWv\020900Veports&spe s4\tra mittal.do Bassett Creek Water Management Commission Planning Process Flowchart Commission Appoints Second Generation Plan Committee Second Generation Plan Committee Prepares Draft Planning Process Prepares Draft Work Plan Develops Proposed Planning Organization Develops Draft Planning Handbook Commission Reviews and Approves Planning Process Reviews and Approves Work Plan Reviews and Approves Handbook Creates Advisory Groups and Defines Responsibilities Steering Committee Develops Agendas, Issues Papers for: Policy Advisory Group (PAG), Technical Advisory Group (TAG), and Citizens Advisory Group (CAG) Prepares Background Information on Work Tasks for Advisory Groups Provides Direction for Advisory Groups Prepares Draft Implementation Strategies Prepares Draft Capital Improvement Plan Provides Periodic Updates to Commission Obtains Periodic Input From Commission Citizens Advisory Group Technical Advisory Policy Advisory Group Develop Public Information Program Group Develop Policies Hosts Public Meetings on Planning Process Address Technical Issues Establishes Performance Monitoring Financing Plan Steering Committee Review Policies and Strategies Proposed by TAG, CAG, PAG Drafts Plan Commission Coordinate Agency Stakeholder Review Respond to Comments Review/Revise Plan Conduct Public Hearing on Proposed Plan Approve Plan To: Bassett Creek Water Management Commission From: Barr Engineering Company Subject: Bassett Creek WMC 2nd Generation Plan Process Date: June 16, 2003 Project: 23/27 0512003 060 Memorandum This memorandum presents the process for the review, revision, and completion of the Bassett Creek WMC 2nd generation plan Commission review of draft plan (July 2003 draft) The draft plan was distributed to the Commissioners, alternates, Technical Advisory Committee, and Policy Advisory Group for informal review. The draft plan will be discussed at the Commission's 1, meeting. The draft plan will be revised in response to the Commission's comments. ,V4 Seer First (60 day) formal review of draft plan This is the first step in the formal review process. The revised draft plan will be sent to the Commissioners, alternates, member cities, Hennepin County, the state review agencies (Minnesota Department of Natural Resources, the Minnesota Pollution Control Agency, Minnesota Department of Agriculture, and the Minnesota Department of Health), the Metropolitan Council, the Minnesota Board of Water and Soil Resources, and the Hennepin Conservation District for the plan's first (60 - day) formal review. The Commission may also send the plan to other stakeholders for review. Respond to Comments after 60 -day review The Commission must respond in writing to any concerns expressed by the reviewers within 30 days of receipt of the comments. Presentations to Cities (Optional) During or just after the 60 -day review, the Commission could present the draft plan to the cities. This is an optional task, not required by state laws or rules. To: Leonard Kremer From: Karen Chandler Subject: Bassett Creek WMC 2nd Generation Plan Budget Date: July 16, 2003 Page: 2 Public hearing on draft plan The Commission must hold a public hearing on the draft plan between 30 and 45 days after completion of the 60 -day review. Second (45 -day) formal review of draft plan The draft plan will be revised in response to the comments received during the 60 -day review, the city presentations (if done), and the public hearing. The revised draft plan will then be submitted to the state review agencies, the Metropolitan Council, the Minnesota Board of Water and Soil Resources, the Commissioners and alternates for review (city review is not required at this point). Review comments The Commissioners will review the comments received during the 45 -day review of the draft plan. Third/final (90 -day) formal review of draft plan The draft plan will be revised once more in response to comments and submitted to the Minnesota Board of Water and Soil Resources for final approval (the Commissioners and alternates will also receive copies). Towards the end of the review period, but before the BWSR Board approves the plan, the Commission will need to make an informal presentation to the BWSR subcommittee regarding the draft plan. Publish/distribute adopted plan Once the plan is approved by BWSR, the Commission must adopt the plan, make final edits to the plan, and then publish and distribute the plan. P.\23\27\051\plan\July 16 2003 internal memo re plan process.doc Bassett Creek Park Pond and Bassett Creek South to Duluth Street Project City of Golden Valley August, 2003 Bonestroo File No. 1438-03-100 Bassett Creek Park Pond and Bassett Creek South to Duluth St. Project Table of Contents Page No. I. Project Summary ..................................................1 II Issues and Problems............................................3 III. Goals and Options to Address the Issues ............ 5 IV. Discussions and Recommendations ..................11 V. Conclusions and Next Steps..............................14 Attachments.......................................................15 I. Project Summary This project focuses on a portion of Bassett Creek from Duluth Street to Westbrook Road in Golden Valley. The City identified several issues of concern in this area, which are shown on Figure 1: • Pond provides no water quality benefits to the creek, and requires frequent and ongoing maintenance • Several problem areas of erosion and sedimentation have been identified which affect the water quality of Bassett Creek • There is a need for water quality treatment for runoff from residential areas and from the MNDOT site • Sanitary sewer backup occurs in one house. Much of the land within the project area is city parkland, and includes an oak woodland in good condition. This project included several steps: • Assessment of conditions and issues in the area • Location and quantification of water quality and sedimentation issues • Identification of options that would address the problems in the area • Meetings with neighbors, MNDOT staff, and the City to discuss the issues and options, and determine preferred solutions This report summarizes the issues and problems in the area, identifies the options developed to address the problems, reports the discussions with stakeholders regarding the identified options, and identifies the preferred options recommended to address the problems in the area. Recommendations include the following: • Modify the area of the existing pond by building a berm that creates a continuous creek, and separates the creek from the pond, up to a 5 or 10 -year storm event. Increase the pond area to the south to compensate for the loss in flood storage. • Use bioengineering techniques to reinforce the berm and adjacent creek banks. Plant the pond with native vegetation, and create a buffer of native vegetation around the pond. • Complete bioengineering improvements to the identified erosion areas, giving a priority to areas near the pond and immediately upstream of the pond. • Work cooperatively with the Minnesota Department of Transportation (MNDOT) to create a water quality pond immediately west of the MNDOT facility. Based on these recommendations, the City will complete plans and specifications for this project, and implement the proposed improvements. Neigborhood storm sewer needs pre-treatment before entering creek. City inventory identified erosion areas along Bassett Creek. t4t. 70 Created pond is an ongoing maintenance problem for the city. Runoff from MNDOT property contributing volume and sediments creek without pre-treatment. Oak woodland is in good condition and includes large maple trees. Bassett Creek Pond and Bassett Creek North to Duluth Street Project Nt0aMc6 Acatla[a Feet 150 0 150 j:/gis/marketing/sp999-03-001. apr II. Issues and Problems A. Existina Pond The existing pond within Bassett Creek was created by a local developer during the 1950's. Neighbors who have lived in the area for over 40 years reported that the developer of the homes adjacent to the pond created it by dredging the creek to form a "lake" that would be an amenity to homes developed in he area. Due to its location within the creek channel, the pond demands a high level of maintenance from the city. As the creek flow enters the pond, it slows dramatically, dropping its sediment load and forming a delta at the upstream end of the pond. Unfortunately, this does not provide an overall water quality benefit to the creek. As the water leaves the creek, it picks up speed and is able to pick up and transport more sediment in the reach below the pond. The delta within the pond is highly visible and unsightly, and requires annual removal by the City. The normal water level in the pond is 854.56'. Modeling completed for this project indicated that during a ten-year storm event, the pond bounces to 860.02', and in a 100 - year event it bounces to 860.85. B. Erosion and Sedimentation The City of Golden Valley completed an inventory of erosion sites in this portion of Bassett Creek in 2001 and 2002. Bonestroo staff used this inventory and gathered additional information on the erosion and sedimentation sites along this portion of the creek. These sites are identified on Figure 2. Sedimentation Sites. As noted in the previous section, the pond is an important sedimentation area (SS -1). Sediment that settles in the pond is the result of both natural and accelerated stream erosion due to urban conditions. Other important contributors of sediment to the creek in this area include the following: • MNDOT property, sites SS -3 and SS -5 • Street drainage: sites SS -2, SS -4, SS -6, and SS -7 Sediment contribution to the creek each year by these sources is estimated as follows: SS -2: 4 tons/year SS -3: 18 tons/year SS -5: 20 tons/year SS -6: 6 tons/year The City recently added a Stormceptor treatment chamber to SS -4, which removes most of the sediment formerly contributed to the creek from this source. Erosion Sites. Erosion is a constant process along all creeks, as the outside banks are gradually worn by flowing water, and sediments are deposited along the inner banks. A combination of factors increase erosion on creeks flowing though urban areas like Bassett Creek, including increased flows during storm events due to high levels of impervious surface in the watershed, and changes in vegetation that replace native deep-rooted vegetation with shallow rooted species such as turf grass that do not help to 3 I I Nr------� 'I I I > I oN ) p I I7 I I I o Westmore Way — -- � �)t{A• \\ \apo, %% / / as _rs' rh it, RI 11WW1' P '— —f--------i---- `� ' � I $ I ----------I I � II o I I ® I I I I / I II L� to o I � II cP ' II I II (;I. II =1 r —' I'-!1, — "$ I " I p, m ; I (n m I I I I I r II I I In I I �N-------- JI ------------I I I 11 I R.L.S. No. 331 I I I I 1 8 I " $ I I I I I II \ a I I I I II IS I I I I i Leet I GOLDEN VALLEY MINNESOTA Banestroo st. veal orn� n �1e Rosene 2335 West Highway 36 W 6 BASSETT CREEK POND Anderlik & St. Peal, MN 55113 EROSION/SEDIMENT SITES Associates Phone: 651-636-9600 s aNJttm Fax: 651-636-1311 o)rt - .....ee.mee.m.Olox6l�aG. �aYK. wvo[Rx a ♦uWUR K ]eN GR ut. M. IR hold bank material in place. Figure 2 identifies the primary erosion sites identified by the City and Bonestroo staff. The most significant sites are within the pond (Erosion Sites A and B) and just upstream of the pond (Erosion site C). Problems associated with each site are as follows: Site A – shoreline erosion from high flows, water fluctuation, saturated soil, and turf grasses with poor root structure Site B – shoreline erosion from water fluctuation, saturated soil, and turf grasses with poor root structure Site C – stream bank erosion caused by high flows, naturally steep banks, and poor root structure of bank vegetation Site D – erosion due to unstable stream channel—a new, straighter channel is being created in this area, and the oxbow is being abandoned Site E – stream bank erosion from high flows, naturally steep banks, and poor root structure of vegetation on banks Site F – stream bank erosion from concentrated flows at the culvert in this area and naturally steep banks. Photos identifying the sedimentation and erosion sites are included on the pages that follow. C. Sanitary Sewer Backup Problem City staff indicated that the home located at 2160 Zane Avenue is subject to sanitary sewer backups. These problems are related to the sanitary sewer service in this area, which is a gravity flow system. Analysis indicated that the difference between the existing walkout elevation of this home and the sanitary sewer invert elevation is approximately 1.6', which indicates that sanitary sewer flow backup can occur during high sewer flows or during a surcharge condition between manholes 1336 and 1427 in this area. Identification of issues, site survey, and analysis were completed during March -May, 2003. The next section discusses options and recommendations developed to address these issues. 5 a FE4 O 0 PEA O W w 9% n ��I w 9 w .0 O 95, 24 O 4o O 400 .O W E .F.( 'tz W 0 ti µyl 13 r .e f ti µyl 13 III. Goals and Options to Address the Issues A. Project Goals The City identified the following goals for its efforts to address the issues identified in the project area: • Improve water quality protection for Bassett Creek • Control unnatural erosion occurring along the creek channel • Minimize maintenance needs in the area • Prevent future flooding at 2160 Zane • Use the site as a demonstration area for best management practices • Create an attractive landscape and improved habitat in the park and for neighbors along the creek Bonestroo staff identified a variety of options for meeting the goals in this area, and discussed the pros and cons of each approach with City Staff, neighborhood residents, and the City's Environmental Commission. These options are described in the sections that follow. B. Pond Options Two options were developed for modifying the existing pond within the creek. Options are shown as Pond Option 1 and Pond Option 2 on Figures 3 and 4. Both options include creation of a berm that will separate the creek channel from the pond area. The berm will provide protection for the creek in all storm events up to the 10 -year event. The creek will no longer lose velocity in this area, and thus sediment will no longer drop in the pond area. The berm and opposite bank within the new pond will be shaped with gradually slopes, and planted with native species with deep root structures to bind the soil and stabilize the slope. Biodegradable coconut fiber mat or biologs would be used with the plantings to assist in slope stabilization and allow vegetation to take root around the pond. These options for slope stabilization are illustrated in the Attachments, Figures Slopes along the creek will require stronger armoring techniques to prevent erosion due to the velocity of creek flows. These areas would be armored using cribwalls or riprap with native plantings (Figures in the Attachments). Cribwalls can be constructed with at almost 1:1 grades, requiring less cut back of banks than the option using riprap and native plantings (2:1 slope maximum). Pond Option 1 includes maintaining a pond to the east of the berm. The pond would be planted with native aquatic species and surrounded by a buffer of native grass and wildflower plantings. The current pond area will be expanded to the south on park property, to compensate for flood storage area lost by creation of the berm. This expanded area may also include a sediment area to trap sediments from SS -2 and SS - 3. While the pond will continue to provide habitat for ducks and other wildlife that the neighbors enjoy, it will not be as large or as open as the current pond. It will no longer 0 1 s�7 ppp`} O 0 ^ i tn C ` O 3 OD,00 ¢5 OOCVI a U) wo z Z o a- y wo >: w W v O Q W a V) z m 1/3801100FO1.DW0 SMCEf -.m F{G 3 a El o F 202 WOw O p a� �ti1 FF�� IIOy1 UDLLZJJ maw � In, pvi �m6Vl u Wig- w � O GI M MOS l0 q n tD -,MD y O 0 Z D M S f 1D .� 7 � to - d 10 y :3 10 , a a (D y, L c x b U) M Nam N O 0 ^ i tn C ` O 3 OD,00 ¢5 OOCVI a U) wo z Z o a- y wo >: w W v O Q W a V) z m 1/3801100FO1.DW0 SMCEf -.m F{G 3 Wo �.ol Z Zo ,' C a' N • ' ` Y z _w o W v o \ J W a Z U) Z m J Z V � 43801100FO1.DWC SNEE.T NUYBEn FIG 4 z va.0 Sao ci mop d FFo �IIaJJg z � �+ i o S Mai M O O rnz�niDi � V La v Lnc x b {A m Lf) = N a d Wo �.ol Z Zo ,' C a' N • ' ` Y z _w o W v o \ J W a Z U) Z m J Z V � 43801100FO1.DWC SNEE.T NUYBEn FIG 4 be continuously flushed by creek flows, but will depend on storm runoff for water and flushing. The pond will be relatively shallow, and ringed by vegetation. The City will also require that an unmown vegetated buffer be maintained around the pond. These changes will improve the habitat quality of the pond, but will change its appearance. Pond Option 2 suggests filling the pond area to the east of the berm, and planting with native grasses and wildflowers to create a meadow. Since the current pond provides no water quality benefit to the creek, this will not have a negative effect on the water quality of Bassett Creek. This option would eliminate the current habitat and aesthetic elements of the pond, but would return the area to its pre -pond condition, and may be more acceptable to those that are concerned about the look of a highly vegetated pond, potential algae growth, mosquitoes, or other potential negative aspects of the pond suggested in Option 1. It would also be a very low maintenance option for the City. MNDOT Pond. The MNDOT site contributes a high amount of sediment to Bassett Creek, and includes no water quality treatment facility at present. A sizeable flat area exists immediately west of the MNDOT property, between the fence and existing trail. The area is currently covered with vegetation of low value—non-native grasses, shrubs and small trees. The area west of the property offers an opportunity to create a pond that would capture sediment from the MNDOT property and remove this sediment source from the creek. The proposed pond is shown in Figure 5. The pond would capture runoff from the existing pipe at SS -5, which collects storm water from about 13 acres of the site. The pipe at SS -3 could be rerouted to run to the pond as well --this pipe collects storm water from about 0.7 acres. The primary advantage of re-routing the pipe at SS -3 would be the opportunity to combine all of the site runoff from the MNDOT site into one outfall to Bassett Creek. Relocating this runoff would also remove the existing outfall from the neighborhood pond, and relocate it to an area under MNDOT control. The proposed pond maximizes the size available in this location—it is approximately .4 acres in size at the normal water level. As currently size, the pond would provide approximately 84% removal of suspended sediments that currently leave the site. If the pipe at SS -3 is not re-routed to the pond, the difference is negligible, since this collects drainage from only a small portion of the site. The current outfall to the creek from SS -5 is in very poor condition, probably due to salt exposure. This outfall should be replaced, and its condition suggests that the entire pipe may need to be replaced. It may be best to complete this work at the same time that the area is disturbed for pond construction. The pond area is currently within the City's Bassett Creek Park. The City proposed creation of the pond on its property, to be maintained by MNDOT. C. Shoreline Stabilization Shoreline stabilization at erosion sites along the channel can be accomplished using a variety of techniques, such as Vegetated Geogrids, Crib Walls, and Rip Rap with Plantings (illustrated in Figures 1-5 in the Attachments). Each technique has pros and cons for use on this site. For example: E fn�� � ~ �•r_I � .: red �::.. I _.. � -. r own etegt � � � � , •tea '• s TF77771 • � ; � . ' sue _ � � ,f� . r„�r;" a t9�� ��=) in � l a _ .. -_. � ;� -.�. %� • 9} EYI88 — r - f > a`�h • e L IL nIgA, •�M,t WL _ 0.168 WeetbPook Road ! Atli a . • Geogrids are typically the most expensive technique among the three illustrated (up to $300 per lineal foot) due to high labor inputs. Rip Rap with Plantings is usually the least expensive technique due to lower labor requirements. • Crib walls and vegetated geogrids can be constructed with less cut back of existing slopes required for stability. They may be constructed on nearly 1:1 slopes or 1.5:1 slopes. • The Rip Rap with Plantings technique would require some cut back of existing eroded slopes to a 2:1 slope or shallower, thus reducing the area of parkland. • All the bioengineering options share the advantages of natural appearance over older stabilization techniques. • Vegetation included in these options helps to slow stream velocities and encourages the deposition of sediment along stream banks. D. Sanitary Sewer Backups at 2160 Zane Several options were identified for addressing the sanitary sewer issue at 2160 Zane. Based on observation that existing private ejector pumps used on other homes in this area are working well, it was agreed that the best solution to improve the sanitary sewer service to this home is to consider an ejector pump system and eliminate the gravity sewer with a gate value. A variety of options exist for installing the ejector pump system. These options will be reviewed with the property owner. Additional information regarding solutions to the flooding problem is included in the Appendix. 11 IV. Discussions and Recommendations A. Neiahborhood Meetin A neighborhood meeting was held on June 16, 2003 at Golden Valley City Hall. Over 50 percent of the residents in the immediate neighborhood attended the meeting. Consultants and staff presented a summary of issues and problems in the area, and described the options for the pond and creek in detail. Both the pros and cons of each option were presented. A lively discussion session with residents followed, with residents providing additional information on creek conditions and problems, as well as insights into the history of the area. The residents reached a consensus on preferences for improvements in the area. Their recommendations included the following: • Residents preferred Pond Option 1, which retains the pond east of the berm, rather than the Meadow Option. • Residents suggested that the pond could be expanded to the south, on park property. • Neighbors favored the addition of a water quality pond near the MNDOT property, rather than continuing or expanding the storm water cleaning function of the existing pond. • Residents indicated concerns that the pond overflow be carefully controlled, so that slopes are not eroded during large storm events. • Residents said that significant trees in the park should not be lost due to creation of the ponds. • Residents near Erosion Site D indicated a preference to keep the newer, straighter creek section rather than routing the creek to the oxbow, so that their views of the creek and wildlife are preserved. • Residents requested that views of the creek be considered as the City plans for erosion control at the sites identified on the creek. Cutting back slopes as a part of constructing these improvements may help to maintain views. • Neighbors expressed concerns about the maintenance of native vegetation to be installed with improvements. City staff indicated that the City contracts with a company that specializes in vegetation restoration for maintenance of such areas. • Neighbors requested that a second meeting be held in August, to review the plans developed for the area, and that plans be provided in an 8-1/2 by 11 format that could be shared with residents who are unable to attend the meeting. B. Meetings with MNDOT City and Bonestroo staff met with MNDOT staff to discuss water quality issues in creek area. Staff presented the analysis identifying the MNDOT facility sediment contribution to the creek, existing conditions in the area, and options for improvements proposed by 12 the City, including the potential pond near the MNDOT property. Staff also provided a costs estimate for the proposed pond (Table 1). MNDOT staff agreed that the pond would be valuable in protecting the water quality of Bassett Creek, and that the cost was reasonable for the improvement that could be realized. They identified some potential options for using MNDOT resources to fund this improvement in cooperation with the City project in the area. These included the Municipal Cooperative Agreement Program and MNDOT Metro District Program Committee. They agreed to present the project, including it's potential costs and benefits, to potential funding sources. The MNDOT staff also identified the following issues to be addressed as final plans for the project are developed: • Is the proposed MNDOT pond an allowed use on City park property? Some types of park acquisition funds or easements could prohibit this use. City staff and attorney will research this issue. The plans and cost estimate should include a gate and paved access for MNDOT equipment that would maintain the site. The City and MNDOT will need to develop a cooperative agreement for financing and maintaining this improvement. 13 IV. Conclusions and Next Steps Based on the analysis and discussions completed for this project, the following improvements are recommended to address the problems identified in the area and meet the City's goals: • Modify the area of the existing pond by building a berm that creates a continuous creek, and separates the creek from the pond, up to a 5 or 10 -year storm event. Increase the pond area to the south to compensate for the loss in flood storage. • Use bioengineering techniques to reinforce the berm and adjacent creek banks. Plant the pond with native vegetation, and create a buffer of native vegetation around the pond. • Complete bioengineering improvements to the identified erosion areas, giving a priority to areas near the pond and immediately upstream of the pond. • Work cooperatively with the Minnesota Department of Transportation (MNDOT) to create a water quality pond immediately west of the MNDOT facility. Construction plans and specifications will be completed during the summer and early fall, 2003. Construction is expected to occur during fall and into winter, 2004. Plantings and any final construction is anticipated to be completed during spring, 2004. 14 Attachments 15 �iTION � +���iL MfCT in R®ssno '� Assoc6at-s Of-noH L� c slacasna 6t�,0CmhD lIAr/EY oF-n Dt—i 3: VbIIETAT ETD CPEO G, a' T.D fl®nazlra® ®amus Engineers & Mchit&--ts 51�MP?5 (Pflo"5, /q.tr.>toP- 5aL...� �fmktt,-. Tmr,j4-- V 1 Y S &/�-A P� 1 V"Ati[,, 'Fb�— Rossne C Andarlik gc "'� to L-0 &Ih WIL4,0W STA , i I)NVETv `rP ww ls4 PIF - v E�A ri T?-� N -►v c --z-7 6T'Tlory 5 . All\] E r� WILLO 00 " T,Vr �kvl DE ovWSQDr'i G T7? -D L. DN z2L-0 fr-- WIU'O W t)TAl ik-N1,► a 0-9— L-7�,e2s b -p -j T LAI\� —F� �\j (�,, Z�-7 PABonaserco INDS R®ssna AnderEk e, Engineer. & Axhif&fs JA Bonestroo Rosene Anderlik & Associates Engineers & Architects May 22, 2003 Mr. Jeff Oliver City of Golden Valley 7800 Golden Valley Road Golden Valley, MN 55427-4588 Bonestroo, Rosene, Anderlik and Associates, Inc. is an Affirmative Action/Equal Opportunity Employer and Employee Owned Principals: Otto G. Bonestroo, P.E. • Marvin L. Sorvala, P.E. • Glenn R. Cook, P.E. • Robert G. Schunicht, P.E. Jerry A. Bourdon, P.E. • Mark A. Hanson, P.E. Senior Consultants: Robert W. Rosene, P.E. • Joseph C. Anderlik. P.E. • Richard E. Turner, PE. • Susan M. Eberlin, C.P.A. Associate Principals: Keith A. Gordon, PE. • Robert R. Pfefferle, P.E. • Richard W. Foster, PE. • David O. Loskota, P.E. Michael T. Rautmann, P.E. • Ted K. Field, P.E. Kenneth P. Anderson. P.E. • Mark R. Rolfs, PE. • David A. Bonestroo, M.B.A. Sidney P. Williamson, P.E.. L.S. • Agnes M. Ring, M.B.A. • Allan Rick Schmidt. P.E. • Thomas W. Peterson, PE. James R. Maland, P.E. • Miles B. Jensen, PE. • L. Phillip Gravel III, P.E. • Daniel J. Edgerton, P.E. • Ismael Martinez, P.E. Thomas A. Syfko, P.E. • Sheldon J. Johnson • Dale A. Grove, P.E. • Thomas A. Roushar, P.E. • Robert J. Devery, P.E. Offices: St. Paul, St. Cloud, Rochester and Willmar, MN • Milwaukee, WI • Chicago, IL Website: www.bonestroo.com Re: Bassett Creek Park — Sanitary Sewer Services Our File No. 1438-03-100 Dear Jeff: Attached are plan/profile sheets (C401, C402) for the existing sanitary sewer in Zane Avenue, Westbrook Road and Vale Crest Road in the Bassett Creek Park Area. We have noted the existing sanitary sewer profile, critical walkout elevations and homes with existing private sanitary sewer ejector pumps along with the year they were hooked up/connected. The existing private ejector pump information is based on your research as noted in your May 2, 2003 email. Based on our research and reviewing walkout elevations, it appears the home at 2155 Vale Crest Road may also have an ejector pump. The purpose of our sanitary sewer review for this area is to document the sanitary sewer system and explore options to improve the sanitary sewer service at 2160 Zane Avenue. Presently the sanitary sewer service is gravity, however a gate valve is located on the service line. The purpose of the gate valve is that during high sewer flows, the gate valve can be closed to prevent sewer back-up into the home. The difference between the existing walkout elevation and the sanitary sewer invert elevation is approximately 1.6', which indicates sanitary sewer flow backup could occur during high sewer flows or during a surcharge condition between MH 1336 and 1427. At our meeting on May 2, 2003, we discussed many options how conditions could be improved to provide sanitary sewer service to this area. However, based on our discussion and the fact the existing private ejector pumps are located in this area and have been working fine, it was agreed that the best solution to improve the sanitary sewer service at 2160 Zane Avenue is to also consider an ejector pump system and eliminate the gravity sewer with gate valve. Different options are available based on how the ejector pump system could be installed dependent on the property owner preference. It's suggested the different options be reviewed with the property owner in accordance with City policy. Please review and we can discuss if additional study is required. Yours very truly, Iq'// Mark A. anson MAH:crw Copy: Jeannine Clancy, Al Lundstrom, Merlin Thorn, Tom Klatte — Golden Valley Sherri Buss, John Smythe 2335 West Highway 36 ■ St. Paul, MN 55113 ■ 651-636-4600 ■ Fax: 651-636-1311