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03-29-99 vMINUTES OF THE WORKSHOP MEETING OF ATLANTIC BEACH CITY COMMISSION HELD IN COMMISSION CHAMBERS AT 7:15 PM ON MONDAY, MARCH 29, 1999 Present were: Suzanne Shaughnessy, Mayor Richard Beaver, City Commissioner Mike Borno, City Commissioner John Meserve, City Commissioner (Arrived 7:30 pm) Theo Mitchelson, City Commissioner Stormwater Review Committee Members Present were: Bob Kosoy Stephen Kuti J.P. Marchioli William McGee Donald Phillips Albert Rabassa Sylvia Simmons Hope VanNortwick Also:Maureen King, City Clerk The meeting was called to order and the invocation offered by Mayor Shaughnessy. The meeting was held for the purpose of reviewing the preliminary design report prepared by R-A-M Professional Group for design modifications to the proposed core city utility improvements, and stormwater collection and tide water control improvements. Wayne Reed, President of R-A-M, introduced his project team and briefly reviewed their tasking. Dr. Marshall explained their approach to the task and reviewed historic drainage patterns. He said that R-A-M had used modeling which had been done by both England, Thims& Miller(ETM) and Camp, Dresser & McKee (CDM). He discussed in detail various modeling tables and calculations which they had done based on existing conditions and with the addition of pumping station(s) and upstream management. Dr. Marshall presented options for a gravity system and a system using pump stations, and reviewed the downstream impact of both systems, and said he felt the city should strive for a system to accommodate a 10-year, 24-hour storm. Dr. Marshall presented the stormwater management recommendations of the R-A-M team, as follows: 1) If the city desires to maintain the level of the Selva Marina Lagoon to between 2.5 -3.5 feet National Geodetic Vertical Datum(NGVD), the recommendation of the R-A-M team is to implement the pumping alternative, if the downstream impacts can be mitigated. Page Two Minutes - Commission Workshop March 29, 1999 2) However, if the desire of the city is to put in place a stormwater management system that provides an improved level of service compared to the ETM designed system, is comparable to the level of flood protection provided to most other coastal Florida communities, and saves about $8 million over the pumping alternative, the recommendation of the R-A-M team is to implement the gravity driven alternative. 3) If the City desires a pumping solution and is willing to relax the project criterion of a 2.5 - 3.5 feel NGVD level in the Selva Marina Lagoon, it is recommended that the City direct the consultants to develop a pumping alternative for only the Core City basins (which is outside the current scope of services). Dr. Marshall presented preliminary cost estimates for each type of system. He then reviewed the open areas and parks and presented the options for Howell Park and Johansen Park Frank Gray then presented various selective value engineering solutions for the core city area, which included inverted crown roadways, swales, curb and gutters, and ribbon curbs. He pointed out that R-A-M had recommended replacing much of the Miami curb and gutter in the ETM design with ribbon curbs,which would result in cost savings. However, each street would have to be considered individually as options may not be suitable for all streets. Jim King then reported on measures that R-A-M would take to preserve trees. He said that unique, or specimen trees had been identified and while some trees would be lost, R-A-M would meander pipes where possible to minimize the damage to root zones. Also, they would recommend root pruning in the root zone area to provide clean cuts and minimize damage. Dr. Harvey then addressed water quality evaluation and presented tables illustrating the amount of pollutants which would be removed using the various options presented. He felt that both the gravity system with an exfiltration system for areas east of East Coast Drive, as well as the pumping option would easily meet the requirements of the St. Johns River Water Management District. Mr. Reed felt that R-A-M had addressed the RFP and had identified options which, if implemented, would enable the city to meet the objectives of this project. The R-A-M team then responded to questions from the City Commission. Commissioner Borno inquired if a tide water control device could be placed at Wonderwood Road where the new culvert would be installed. He felt a manually operated flood gate at this location would provide for increased capacity, possibly at a reduced cost. Dr. Marshall felt this location would work but indicated he had located the tide water structures at other locations only because they were within the city boundaries. Commissioner Borno also noted that using the ETM system of curbs and gutters, the streets were lowered considerably and Mr. Gray confirmed that the streets would not be lowered using the ribbon curb system, again resulting in cost savings. Commissioner Page Three Minutes - Commission Workshop March 29, 1999 Borno also inquired regarding the feasibility of burming at the golf course and was advised that this would be feasible on the west side of the lagoon; however it was felt that the bridge should be widened as it presented an obstruction. Commissioner Borno inquired regarding the impact to the project if the city was willing to increase the level of Selva Marina lagoon and it was felt that this would be of considerable benefit to the project as it was very difficult, especially with the gravity system, to get the level of the lagoon to the desired 2.5 - 3.5 feet. Commissioner Mitchelson inquired regarding the feasibility of installing rectangular shaped pipes, with weirs. Dr. Marshall explained they had tried to parallel the ETM efforts for easier comparisons; however,the large pipes may be able to be replaced with more economical sections. Commissioner Mitchelson also inquired regarding one-way streets and swales but it was explained that because of the space available and the depth of the swales,which would kill trees, this idea had been abandoned. On behalf of the Community Development Board, Commissioner Mitchelson also inquired regarding the percentage of impervious surface the R-A-M team had used in their calculations and Dr. Harper said he felt a 50% assumption had been used. 1111 Commissioner Mitchelson also inquired regarding ribbon curb which he felt would slow the movement of water and was advised that ribbon curb would not move the water as quickly as the Miami curb but would protect the edge of the road; also, more inlets would be required and they would be tailored to individual situations. Commissioner Mitchelson inquired what the inlet would look like and following discussion, R-A-M agreed to fax an illustration of the inlet to be distributed to the City Commission. With reference to an automatic tidal control device, Commissioner Mitchelson inquired regarding the impact of power outages, and Dr. Marshall said they were charged with coming up with an automatic system but he felt that a manual control would be required to deal with power outages. He said they preferred to use a manual system for this project but it could be automated if the city chose to do so. Commissioner Beaver inquired regarding the size of ribbon curb and was advised it was 9-inches wide and would be flush with the asphalt except when a yard which was lower than the street when the curb would then be raised about 3-inches. He inquired regarding the impact of future paving on ribbon curb and Dr. Marshall said that R-A-M would recommend milling and repaving rather than overlayment. Commissioner Beaver asked for some information regarding opening up Sherman Creek, i.e. where to connect, pipe sizes, etc. Three alternatives were given (1) an inlet structure at the north end of Selva Marina lagoon near Saturiba Drive, (2)use an area at the entrance to Sevilla Gardens, or (3) along the north side of Fleet Landing near the crossing to A-1-A and connect to the Sherman Creek flood plain, and it was felt that the best solution may be a combination of all three. Page Four Minutes - Commission Workshop March 29, 1999 Commissioner Beaver commended R-A-M on their innovative suggestions to preserve trees and inquired who would do inspections to make sure that proper procedures were followed. Mr. King explained that he would recommend that an arborist or an urban forester be involved throughout the construction process, especially during excavation. Commissioner Beaver also inquired regarding the level of maintenance which would be required for the exfiltration system and was advised that sumps would be provided in catch basins, and they should be kept clean. They would be located close to the ocean where they work best and could be cleaned on an annual or semi-annual basis using a jet-vac truck. It was also pointed out that New Smyrna Beach, Ormond Beach, and Daytona have exfiltration systems and city staff could contact them with any questions they may have regarding these systems. Commissioner Beaver also inquired regarding the burden on the system based on the amount of impervious surface and was advised that there was a direct correlation between the amount of run-off and the amount of impervious surface. Commissioner Beaver asked for additional information regarding comments made earlier about collection systems jogging from one side of the street to the other and was advised that inlets would be on both sides of the road but the piping system would be angled to avoid tree roots where possible. Sanitary sewer lines would also be angled to correspond to the drainage pipes. Commissioner Meserve inquired whether the drainage system at Fleet Landing was impacted by tides and was advised that it was impacted by tides and it was suggested that a manually operated tide valve had been proposed at that location for that reason. Commissioner Meserve expressed some concerns about the adverse effect that opening Sherman Creek may have to the Fleet Landing area. He also inquired whether Sherman Creek was large enough to accommodate large pipes. Dr. Marshall explained that to get adequate cover on the pipes it may be necessary to use a"bubble up" structure. He also felt that while Sherman Creek was not very large, there was a broad flood plain on either side. Commissioner Meserve also asked whether a study had been done to see how many trees would be lost on Selva Marina Drive. Dr. Marshall advised that time had not permitted for the level of study they would have liked for this area; however he felt that the Sherman Creek area would provide a large area for flood water storage but additional work would have to be done to determine pipe sizes. Commissioner Meserve also pointed out that the Mayport Crossing shopping center drained to the south through Fleet Landing property and he indicated he would make details of this drainage available to R-A-M if it would be helpful. Commissioner Meserve inquired regarding the proposed drainage structures in Johansen Park. Dr. Marshall indicated that the existing ditch was not sufficient to handle the necessary flow and they would suggest widening and meandering the ditch between trees so there would be no tree loss. Page Five Minutes - Commission Workshop March 29, 1999 Mayor Shaughnessy felt that the proposal presented by R-A-M did fulfill a lot of the goals as outlined in the RFP. She inquired whether the RFP required the flood gates to be automated and was advised that the reference in the RFP requested automated structures, if appropriate. The Mayor said she would withhold any comments or questions regarding the ribbon curb until she had received the drawings which had been requested earlier in the meeting. Using an aerial picture, the Mayor pointed out the Sherman Creek flood plain and noted that it was one-third to one-half the size of the golf course. She felt that the disconnection of Sherman Creek should not have happened and this situation should be corrected. She felt that this area was important to Atlantic Beach drainage and should not go unused. When asked why the creek could not just be reopened at its original location, it was pointed out that the creek had been filled and there was now construction between Selva Marina Lagoon and Sherman Creek, and therefore a new route would have to be found. Mayor Shaughnessy suggested opening dialogue with St. Johns River Water Management District regarding reopening Sherman Creek. She also pointed out that the lowest point in the drainage chain is on the golf course and suggested opening dialogue with the Board of Directors of Selva Marina Country Club regarding possible solutions. The Mayor also noted that only 30% of the water coming into Selva Marina Lagoon was from the old city area. Dr. Marshall indicated that by opening Sherman Creek and removing some of the upstream constrictions, including Howell Park by-pass, along with piping in the numbered streets, the flooding in homes would be alleviated;however,without the Howell Park by-pass and conveyance pipes, there would be no improvement south of Plaza. Dr. Marshall, however, pointed out that while the concept of this system was sound, the details of the system would require further fine tuning. With the exfiltration system to the east and since the water would already be filtered when it reached Howell Park, the Mayor inquired why the low lying areas of Howell Park could not be used as temporary storage. Dr. Marshall pointed out that there was a major bottleneck at that area. He said that Howell Park was not large enough to accommodate the runoff and it was, therefore, necessary to by-pass Howell Park in order to reduce the level of water in the park, thus allowing the pipe sizes on the numbered streets to be reduced. The Mayor inquired if increasing the level of water in Selva Marina Lagoon by 1.5 - 2 feet would make any difference to the project. Dr. Marshall responded that this would help to some extent but would not be as effective as providing additional storage. The Mayor noted that the R-A-M proposal would maintain the level of the existing road beds which would be beneficial for purposes of tree protection; however she felt that in order to lay utility lines, the roots would be disturbed in any case. Jim King responded that most of the trees were on private 411/Page Six Minutes - Commission Workshop March 29, 1999 property and the pipes would be installed as far as possible from the trees. Also equipment would be used to cut roots rather than using a backhoe. He also listed other measures which could be taken to protect trees. Further discussion ensued and Commissioner Borno inquired whether placing flood gates on Wonderwood would help, (if an agreement could be reached with Jacksonville), and if it was felt that additional modeling should be done in this regard. Commissioner Borno also inquired whether a 10 year, 24 hour project would eliminate all back year flooding and it was felt that in some cases backyard pumps would still be necessary. At this time the Mayor called a recess. The meeting reconvened at 10:20 PM. and comments from the audience were invited. Stephen Kuti indicated that he was very upset until he heard the R-A-M presentation. He said he was particularly upset about proposed 60-inch pipes on Selva Marina Drive; however, during the questions from the City Commissioner, he found that many of his concerns were addressed. He indicated that he agreed with opening up Sherman Creek. He said he had discussed briefly with Dr. Marshall the possibility of using smaller pipes with a small pump on Selva Marina Drive and he said that Dr. Marshall indicated that this was a good observation. Albert Rabassa expressed concerns that flooding may be controlled in the core city but may be moved to another area. He noted that Creekside Drive currently experiences flooding and he also pointed out that Sevilla Gardens was not shown on the map being used by R-A-M and he felt that an impact study was needed on the area where Creekside would flow into Sherman Creek. Mayor Shaughnessy,however, pointed out that the most likely connection to Sherman Creek would be north of Fleet Landing. Mr. Rabassa was also concerned regarding the proposal to install very large pipes along Selva Marina Drive, which he felt would result in major tree loss. Harold Brodeur expressed concerns regarding flooding of the Selva Marina Lagoon, which he felt would create flooding problems for residents on Sevilla Boulevard. Mayor Shaughnessy again reviewed the three options which had been suggested for opening Sherman Creek and indicated that it would be extremely unlikely that 60-inch pipes would be installed in Selva Marina Drive. William Friedmann, expressed concern regarding potential flooding in the vicinity of his home at 1898 Selva Marina Drive. He said he had installed a sump pump to alleviate current flooding during heavy rains but was concerned that flooding from the wetlands as a result of opening Sherman Creek, would create additional flooding for him and his neighbors. Page Seven Minutes - Commission Workshop March 29, 1999 Dr. Gregory Powell, P.E., felt that the concept as presented had merit; however, he felt that careful modeling and analysis of Sherman creek should be undertaken before the city signs off on this proposal. He also referred to earlier comments about the possibility of installing 60-inch pipes on Selva Marina Drive, and it was the consensus of the City Commission, that that proposal was off the table. J.P. Marchioli suggested that cisterns to collect rainwater off the roof, would be a solution to the questions regarding the amount of pervious/impervious surfaces to allow. He also suggested that existing culverts be reused as far as possible and noted that while larger pipes provide greater drainage, they also allow a greater amount of drainage to flow back into the system. There being no further discussion, the Mayor declared the meeting adjourned at 10:55 PM. Maureen King Certified Municipal Clerk