Introduction STORMWATER SYSTEM ENHANCEMENT RECOMMENDATIONS

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3 Introduction During the early morning hours on Wednesday, September 24, 2014, the City of South Daytona received over six inches of rain which caused several streets to flood. In addition, there were six single family residential homes that had floodwater infiltrate the living area which resulted in an estimated $38,000 in damage. The map below shows the streets that were flooded in addition to identifying those residential homes that had water in the living area. 1

4 This storm had a severe impact on the coastal cities in Volusia County. The table below shows the total number of residential homes within Volusia County that had flood damage. Single Family Residential Home Damage Taxing Authority Number of Homes with Flood Damage Total Damages Daytona Beach 28 $465,432 New Smyrna Beach 7 $436,927 Port Orange 71 $2,058,133 South Daytona 6 $38,000 TOTALS 112 $2,998,492 The information presented above was compiled using information provided by the Volusia County Property Appraiser and the Community Development Department. Although this City fared better than other municipalities, there are some enhancements to our stormwater system that staff is recommending be completed to reduce the flooding levels of future storms. To be able to recommend improvements to our drainage system, we must first document and understand the stormwater improvements that the City has already completed to reduce flooding. Summary of Stormwater Projects Completed by the City Which Reduced Flooding The City has spent about $20 million on drainage improvements since Tropical Storm Gordon hit in 1994 to reduce flooding City wide. The major projects that have been competed during that time frame include: Aspen Stormwater Control Facility Boston Avenue and Chicago Avenue Drainage Improvements Blaine O Neal Park Pond Sauls Street / Harborside Drainage Improvements Palm Grove Stormwater Improvements Reed Canal Stormwater Control Facility Park of Honor Lake Foxcroft Drainage Improvements Green Street Drainage Improvements Static Stormwater Pumps at Pike Court, Lakeview Estates, Big Tree Shores, Windle Lane, Lantern Park and Sherwood Forest Backflow Prevention Devices City Wide 2

5 Over the years it can be proven that the completion of these projects has undoubtedly reduced the flooding within this City. To demonstrate this point, the table below shows the flood damage caused by every major storm to hit South Daytona since Storm Event No of Homes Flooded Estimated Damage TS Gordon $7.3 million Hurricanes of $315,000 May 2009 Rain Event 8 $158,000 September 24, $38,000 While this City has drastically reduced the number of flooded homes over the years; there still are some enhancements that need to be completed to further reduce the damaging effects of flooding. Proposed Stormwater System Enhancements Drainage systems constantly evolve as the surrounding area redevelops. We learn a little bit more about our drainage system capabilities with each severe weather event we experience. Continually improving our drainage system and adjusting it according to the lessons learned from each storm event is the only way to effectively reduce the destructive power of a flood. There are a total of 10 enhancements that staff would like the City Council to consider for funding to further enhance our drainage system and reduce flooding. The stormwater enhancement recommendations are detailed in the sections that follow which have been tabbed for ease of reference. 3

6 Reed Canal Stormwater Control Facility Weir Gate Equipment Replacement and Enhancement The Stevens Canal is critical in draining the entire central portion of the City. This canal is also responsible for draining parts of Beville Road and the Daytona Beach Municipal Golf Course. When this canal stages at a high level, it causes flooding to adjacent roadways. In 2009, the City completed construction on an 8 acre lake located off Reed Canal Road designed to regulate the level and treat the water in the Stevens Canal. The Reed Canal Stormwater Control Facility, as it is known, contains a pump station designed to lower water levels on command. A picture of the stormwater facility is shown below. 4

7 A rotating concrete weir gate was installed in the Stevens Canal to separate it from Reed Canal during high tide conditions. The weir gate is raised and lowered using an air compressor and inflatable bladders. The gate raises when air is forced into the bags and it is lowered when air is let out of the bags. A picture of the weir gate is shown below for reference. Following the rain event on September 24, 2014, it became advantageous for the weir gate to be lowered to allow Stevens Canal to drain into Reed Canal. The weir gate could not be lowered due to a prior malfunction of both the compressor and inflatable bladders. The gate was finally able to be lowered using improvisation and the canal drained rapidly. Shortly thereafter the roadways adjacent to the Stevens Canal began to drain. The operation of this weir gate is critical to the reduction of flooding within the central portion of this City. Staff is recommending that the inflatable bladders be replaced along with the air compressor to allow the weir gate to move as was designed. In addition, we are recommending the installation of a mechanical lift on the weir gate so that it can be manually lowered and raised if this type of failure happens again. This mechanical lift will also allow personnel to manipulate the gate during a power failure if one were to occur during a storm. 5

8 Staff has estimated the cost of this equipment replacement and enhancement at approximately $180,000. A cost breakdown is presented below. Reed Canal Stormwater Control Facility Enhancements Item Description 2014 Estimated Cost 1. Inflatable Bladder Replacement $50, Air Compressor Replacement $20, Mechanical Lift for Weir Gate $110,000 TOTAL ESTIMATED COST $180,000 Once these improvements are made to the gate, a reduction of flooding is expected to occur on the streets shown below which flooded during the September 24, 2014 severe rain event. 6

9 Park of Honor Stormwater Pump Replacement In 2008, the City constructed a stormwater pond in what is now known as the Park of Honor designed to reduce flooding within the Western Road area. A picture of this stormwater pond is shown below for reference. The Park of Honor Pond has a small pumping station which must maintain an appropriate lake level to effectively reduce flooding. During the severe rain event on September 24, 2014, the pump station was overwhelmed by the amount of rainfall. The lake level rose and caused flooding on several streets. The pumps within the station must be increased in size to be able to handle severe events with large amounts of rainfall. There are currently two pumps within the station. It is recommended that one of the pumps be replaced with a larger one designed to accommodate large amounts of rainfall. The other pump can remain to maintain the lake level during routine operations. 7

10 Staff has estimated the cost of upsizing one of the pumps within the station at approximately $85,000. A cost breakdown is presented below. Park of Honor Stormwater Pump Replacement Item Description 2014 Estimated Cost 1. Large Pump Purchase Price $75, Pump Electrical Connection $5, Discharge Pipe Replacement and Shoreline Stabilization $5,000 TOTAL ESTIMATED COST $85,000 The pump being replaced from this station will be used at the Duck Pond located on Anastasia Avenue as recommended later in this report. Once a larger pump is installed at the Park of Honor Pond, a reduction of flooding is expected to occur on the streets shown below. 8

11 Lantern Park Pond Construction The Lantern Park subdivision was built without a stormwater pond. The entire subdivision is drained by two outfall pipes which are tied directly to Reed Canal. When Reed Canal is at a high elevation, the subdivision cannot drain. Stormwater runoff backs up into Lantern Drive and floods the road threatening homes. Staff recognized this issue and used a two-phased approach to resolve the flooding here. The first phase involved the installation of two stormwater pumps within the main discharge pipe to force water into Reed Canal. This phase of the work was completed. During the September 24, 2014 rain event, one of these pumps malfunctioned. Lantern Drive flooded but no homes were adversely affected. It is unlikely that the flooding of Lantern Drive could have been prevented even with both pumps working. The second phase involved the installation of a stormwater pond. This stormwater pond, once constructed, would become the lowest point and water would stage there instead of Lantern Drive. The location of the proposed pond is shown on the map below. 9

12 Staff has estimated the cost of constructing the stormwater pond at approximately $241,000. A cost breakdown is presented below. Lantern Park Pond Construction Item Description 2014 Estimated Cost 1. Clearing and Grubbing $18, Construction of Pond $133, Construction of Pumping Station $89,000 TOTAL ESTIMATED COST $241,000 The proposed pond property has already been acquired with grant funds. The City has received a grant for the construction of the pond as well. The pond is scheduled to be installed by the fall of Once the pond has been constructed along with the pumping station, it will reduce the flooding experienced on Lantern Drive. 10

13 Sherwood Forest Stormwater Station Pump Replacement The Sherwood Forest subdivision was built without a stormwater pond. The entire subdivision drains towards a pump station on Sherwood Drive. The location of this stormwater pumping station is shown below. During the September 24, 2014 rain event, this pumping station was overwhelmed with stormwater and Sherwood Drive was flooded. The two pumps within the station must be increased in size to be able to handle severe events with large amounts of rainfall. Staff has estimated the cost of upsizing the two pumps within the station at approximately $90,000. A cost breakdown is presented below. Sherwood Forest Stormwater Station Pump Replacement Item Description 2014 Estimated Cost 1. Pump Replacements $80, Pump Electrical Connection $5, Discharge Pipe Replacement $5,000 TOTAL ESTIMATED COST $90,000 11

14 This project lies in an area that qualifies for a Volusia County Community Development Block Grant. Staff is recommending that the City utilize this grant to complete this project in FY The grant should cover all of the construction costs. The pumps being replaced at this station are interchangeable with the pumps at the sewer lift stations. Therefore, staff is recommending that the pumps being removed from this station be used to replace two of the existing sewer lift station pumps that are much older. Once larger pumps are installed at the Sherwood Forest Stormwater Station, a reduction in flooding is expected to occur within the entire subdivision. 12

15 Windle Lane Stormwater Pond Expansion There are two small ponds located on Windle Lane to manage the stormwater within the back half of the Coventry Forest subdivision. Five years ago, the City installed two stormwater pumps here to maintain the water level in these ponds during a severe rain event. Recognizing that these ponds are undersized, staff recommended that additional property be acquired for pond expansion. The land acquisition necessary to expand the pond was included in the FY budget prior to the September 24, 2014 severe rain event. During that rain event, the two small ponds were overwhelmed and water backed up into the adjacent streets. Staff is recommending that the City proceed with the purchase of the additional land necessary to expand the two small ponds into a larger one. The location of the proposed pond is shown on the map below. The expanded stormwater pond will necessitate the installation of larger stormwater pumps to effectively maintain water levels. 13

16 Staff has estimated the cost of expanding the stormwater pond and replacing the stormwater pumps at approximately $115,000. A cost breakdown is presented below. Windle Lane Stormwater Pond Expansion Item Description 2014 Estimated Cost 1. Land Acquisition $15, Expansion of Pond $40, Pump Replacement and Wiring $60,000 TOTAL ESTIMATED COST $115,000 One of the pumps being replaced from this station will be used at the Duck Pond located on Anastasia Avenue as recommended later in this report. The other pump will remain in inventory to be used as a backup should one of the others fail during a severe rain event. Once the pond is expanded and the larger pumps installed, a reduction of flooding is expected to occur on the streets shown below. 14

17 Jones Street Stormwater Pond Construction Jones Street, behind the City Hall Complex, has a tendency to flood during severe rain events. The water collected in the stormwater inlets here has to make its way underneath US 1 and into the Bellewood Waterway. This distance makes drainage of this street very slow. During that September 24, 2014 rain event, Jones Street was flooded so bad that standard vehicles, including police cruisers, could not make it through. Staff is recommending that the City acquire a small tract of land adjacent to the flooded area of Jones Street to create a stormwater pond. Stormwater can then be stored in the pond instead of Jones Street itself while it makes its way to the Bellewood Waterway. The location of the proposed pond is shown on the map below. The proposed pond is located on a parcel of land currently owned by the White Chapel Church of God. Some parents whose children attend the school located nearby use a small portion of this land for vehicle parking. It is anticipated that if the City were to 15

18 develop a stormwater pond on this parcel, a small parking lot would have to be constructed to accommodate the current condition. Staff has estimated the cost of constructing the stormwater pond at approximately $60,000, excluding the land acquisition. A cost breakdown is presented below. Jones Street Stormwater Pond Item Description 2014 Estimated Cost 1. Land Acquisition To Be Determined 2. Parking Improvements $20, Pond Construction $40,000 TOTAL ESTIMATED COST $60,000 +/- Once the pond is constructed, a reduction of flooding is expected to occur on Jones Street to allow emergency vehicles to pass. This project lies in an area that qualifies for a Volusia County Community Development Block Grant. Staff is recommending that the City utilize this grant to complete this project. The grant should cover most if not all of the project costs. 16

19 Anastasia Rear Yard Swale / Inlet System and Pump Installation at the Duck Pond During the September 24, 2014 rain event, stormwater sat in the rear yards of those homes adjacent to the Duck Pond on Anastasia Drive for several days. The rear yards there are low and the collected stormwater cannot make it to the street or the nearby Duck Pond to drain. To drain the rear yards here, it is recommended that a shallow swale be constructed to direct stormwater runoff towards the Duck Pond. The swale will get deeper as it gets closer to the Duck Pond and may make it difficult to maintain for those property owners. To avoid this situation, a series of inlets are being proposed. This inlet system will be piped to the Duck Pond to ensure proper drainage of the area. The location of the proposed swale / inlet system in relation to the Duck Pond is shown on the map below. Staff is also recommending that one stormwater pump from the existing Park of Honor Stormwater Pond and one pump from the Windle Lane Stormwater Pond be relocated here to effectively manage the water level inside the Duck Pond. 17

20 Rear yard drainage easements will have to be acquired to accommodate the installation of the proposed swale / inlet system and allow for proper maintenance. Staff has estimated the cost of installing the swale / inlet system and relocating the pumps at approximately $65,000. A cost breakdown is presented below. Anastasia Rear Yard Swale / Inlet System and Pump Installation at the Duck Pond Item Description 2014 Estimated Cost 1. Swale Installation $15, Inlet System Installation $40, Pump Relocations and Wiring $10,000 TOTAL ESTIMATED COST $65,000 Once the swale / inlet system and pumps are installed, the rear yard flooding should be greatly reduced. 18

21 Harborside Stormwater Pumping Station The streets within the Harborside subdivision drain into two large stormwater ponds. As the pond levels rise, water enters an overflow structure and is discharged to Reed Canal. When Reed Canal stages at a high elevation, the water inside the stormwater ponds has nowhere to go and floods the adjacent streets. During the September 24, 2014 rain event, the streets within Harborside were flooded because Reed Canal was inundated. To alleviate this condition in the future, staff is recommending the installation of a stormwater pumping station to force this overflow into Reed Canal. Staff has identified a location, lying within a right of way, in which the pumping station could be installed. The proposed location of the stormwater pumping station is shown on the map below. 19

22 The existing masonry wall that surrounds Harborside would buffer noise and prevent any disturbance to nearby homes. Staff has estimated the cost of installing the pump station at approximately $40,000. A cost breakdown is presented below. Harborside Stormwater Pumping Station Item Description 2014 Estimated Cost 1. Wet Well Installation $7, Pump Installation and Wiring $30, Discharge Pipe Installation $3,000 TOTAL ESTIMATED COST $40,000 Once the pumping station has been installed, the water level within the stormwater ponds can be controlled to reduce flooding of adjacent streets within Harborside. 20

23 Biscayne Avenue Stormwater Pipe Replacement The inlets on Biscayne Avenue are connected to the stormwater collection system on Golfview Boulevard. This system eventually drains into the Park of Honor Stormwater Pond. The inlets on Biscayne Avenue are connected to Golfview Avenue with a 15-inch corrugated metal pipe. This pipe is undersized and causes stormwater to flood Biscayne Avenue around the inlets. During the September 24, 2014 rain event, stormwater flooded Biscayne Road due to this undersized pipe and the inundation of the Park of Honor Stormwater Pond. To alleviate this road flooding, staff is recommending the replacement of the undersized 15-inch corrugated metal pipe with a larger 24-inch high density polyethylene pipe. The combination of this increased pipe size and the pump improvements recommended for the Park of Honor Stormwater Pond, identified earlier in this report, should reduce the street flooding here. A map showing the location of the proposed pipe replacement is presented below. 21

24 Staff has estimated the cost of replacing this pipe at approximately $35,000. The larger stormwater pipe will necessitate the replacement of three existing stormwater inlets and roadway restoration on Golfview Boulevard. A cost breakdown is presented below. Biscayne Avenue Stormwater Pipe Replacement Item Description 2014 Estimated Cost 1. Stormwater Inlet Replacement 3@$5,000 each = $15, inch HDPE Pipe Installation $15, Roadway Restoration $5,000 TOTAL ESTIMATED COST $35,000 Once the pipe has been replaced and the pump improvements have been made to the Park of Honor Stormwater Pond, the flooding on this street should be alleviated. 22

25 SCADA Telemetry to Monitor Both Stormwater and Sewer Pumping Stations Supervisory Control and Data Acquisition (SCADA) systems are used to procure data to effectively manage a process such as the pumping of stormwater or sanitary sewage. These systems are capable of monitoring water levels and pump performance inside a sewer lift station or stormwater pond. When the water level rapidly rises or pump performance falls from normal parameters, the SCADA system will alert the appropriate personnel that attention is required at that location. It is recommended that SCADA Telemetry be installed at every sewage lift station and stormwater pumping station within the City. The proposed locations are shown on the map below. 23

26 During the September 24, 2014 severe rain event, the SCADA system would have alerted the Public Works Department that the gate needed to be lowered at the Reed Canal Stormwater Facility before street flooding had a chance to occur. The system would have alerted the Public Works Department that the Pike Court pump had failed so that a portable pump could be installed at a timely manner. The SCADA system would have indicated that the pumps inside the Park of Honor were not lowering the lake level fast enough so that a portable pump could have been dispatched to assist in the drawdown. Getting information in real time will give personnel the time that they need to stay ahead of the floodwaters. There are 26 different stations that are being proposed to be outfitted with SCADA telemetry throughout the City. These SCADA installations at the locations can be phased in starting with the bigger stations, such as the Aspen Stormwater Pump Station, first. Staff has estimated the cost of installing SCADA telemetry at all of the locations at approximately $375,000. A cost breakdown is presented below. SCADA Telemetry Installation Item Description 2014 Estimated Cost 1. SCADA Telemetry per Station $10,000 x 32 stations = $320, Software and Monitoring Equipment $30, Engineering Consultant $25,000 TOTAL ESTIMATED COST $375,000 24

27 Recommended Phasing of the Enhancements Staff is recommending that the proposed enhancements described above be phased in as revenues allow. The table below shows in what year the proposed enhancement projects should be completed based on the severity of potential flooding. Recommended Completion Order of the Projects Project Description Estimated Cost Fiscal Year Reed Canal Stormwater Control Facility Enhancements $180,000 FY Lantern Park Pond Construction $241,000* FY Sherwood Forest Stormwater Station Pump Replacement $90,000** FY Windle Lane Stormwater Pond Expansion Land Acquisition $15,000 FY Pond Construction $100,000 FY Park of Honor Stormwater Pump Replacement $85,000 FY Jones Street Stormwater Pond Construction (excludes land costs) $60,000** FY Anastasia Rear Yard Swale / Inlet System and Pump Installation $65,000 FY Harborside Stormwater Pumping Station $40,000 FY Biscayne Avenue Stormwater Pipe Replacement $35,000 FY SCADA Telemetry to Monitor Pumping Stations (costs can be spread over multiple years) $375,000 FY TOTAL $1,286,000 * The Lantern Park Pond has received grant funding for reimbursement of project costs in FY ** The Sherwood Forest Pump Replacement and Jones Street Pond are eligible projects for the CDBG program. 25