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1. What is a low pressure sewer system? These Systems convey wastewater from your home or business to the regional wastewater treatment facility. Unlike a gravity connection, Low Pressure Sewers use a small pump station located at each house to move wastewater through the transmission system. Low pressure sewers are installed where gravity sewers are not cost effective or feasible, and have been effectively used by NMB for 25 years! 2. How does it work? Wastewater from your home or business flows by gravity into the collection tank aka grinder pump basin. Floats in the Collection Tank send signal to Control Panel to turn on Grinder Pump. Grinder pump macerates the effluent into a slurry and pumps the wastewater through the low pressure force main (pipe) in the public right-of-way. 2

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 Why a Low Pressure Sewer (LPS)system for North Miami Beach?  Developed urban area, properties within district were scattered ( geometry)  Applied a concept used up North for lakeside communities.  1989 established the West Dixie Highway Industrial District 4 main property owners participating: Friendly Ford, Peoples Gas, Santi Brothers, Landmark Chevrolet,. They were large tracts of land or multiple parcels/blocks Project cost was estimated at $260,000 Ground breaking ceremony January 1989  The City designed and constructed the Low Pressure Sewer system 6

System was extended with a second phase in 1991 and a third phase 1996 Today the system is 4 miles long and has 65 grinder pumps connected to it. Each property supplies the power. In 1989 Executed purchase agreement with Environment One Corp (E-One) A 1 hp simplex was $1234.A 1 hp duplex was $2,625 A few Myers submersible grinder pumps were also installed in 1996 In 1998 we migrated to ABS pumps Piranha Grinders- Grinders in general shred to a fine slurry able to pass through a 2” piping. the basins are 48 inches wide, 6 feet tall ( typical) made of fiberglass Able to extend with 12”, 24” or 36” vertical extensions Control panels In 2011 ABS became Hydra Service Pumps 2 hp duplex are the majority of new installs costing around $10,000 each ( off the shelf) 7

1.Lessons learned? It is best to try and standardize the pump type. These are systems and involve more than just a physical pump. 2. Most common problem encountered? The stations for the most part are problem free for the first five years, after that is just proper maintenance of the stations. Starter kits are the most frequently replaced, followed with bad pumps. The main problem with the grinder is no power to the station. This can be due to: ELECTRICAL No power from the building Customer did not pay his FPL bill Breaker tripped or turned off Starter kit needs replacement Blown fuse in the panel MECHANICAL Loss of prime Clogged check valves Pump replacement 3.Life expectancy of GP? year 8

4. Benefits of butt fused pipe. Problems with it? I & I problems are eliminated with this system. Installation at 3 feet of cover, no sloping, flexible, avoid utility conflicts, trees etc. Faster and long run to install. Do not have any breaks other than accidental hit by contractor. It is very challenging to repair without a butt fused machine (hard to repair in case of accidental hit (especially the small diameter pipe). 5. How many calls per week or per month on our LPS system. On average maybe one call every month 6. cost to maintain ? Monthly we try to service the stations one a month with the inspection and cleaning the wetwell with the Vac-truck. 7.How many stations per last count? There are 65. 9

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 Used for 25 years in South Florida – it works in NMB!  Can be cost effective in the right application  Need to establish a maintenance program  Now being used in the keys and Miami Shores Downtown District 20