The Area N3 Committee is happy to inform you that the Sarasota County Utilities Department has “dumped the pumps” and is no longer recommending individual grinder pumps to provide sewer service in our neighborhood.
Somewhat surprisingly, though, the recommended option is not a vacuum system, which had been the main alternative under consideration. Instead, what is being proposed for our neighborhood is an “enhanced gravity system” or “hybrid gravity system.”
On Sept. 5, 2013, five members of the N3 Neighborhood Committee (Peter Gentile, Dave Kaplan, Del Macaulay, Walt Menzel and Peter Houk) met with representatives of the County Utilities Department to hear about this latest proposal. The information that follows is our understanding of the proposal based on that meeting.
What is a hybrid gravity system?
As the name implies, a hybrid gravity sewer system is at heart a traditional gravity system. A gravity system is what most people think of as a “normal” sewer system. Sewage flows downhill from the home through pipes that descend gradually deeper into the ground until they arrive at a lift station. At the lift station, sewage is pumped up to a higher level to continue its flow toward the treatment plant. In a traditional gravity system, lift stations can be 20 feet or more underground and collect wastewater from hundreds of homes.
In a “hybrid gravity system,” there are more (but smaller) lift stations and the pipes are not buried so deeply in the ground (3 to 6 feet, rather than 6 to 20 feet).
For our neighborhood, there will be approximately 6 to 10 “mini lift stations” located underground in concrete chambers serviced through manholes. The manholes will be flush with the ground or street. Near each mini lift station will be an electrical control panel affixed to a chest-high concrete post. The electrical control panels will be the only above-ground component of the system. (Incidentally, these control panels are similar to the control panels that each homeowner would have been required to install to operate the grinder pumps.)
The mini lift stations will be placed inside manholes in the county right-of-way (either under the pavement or in the shoulder of the road). The precise locations of the mini lift stations have not been determined, but the county has identified some potential locations that are minimally intrusive. However, it is possible that at least some of the mini lift stations will be located so that the control panel will be in the right-of-way between two homes (similar to where a utility pole would be sited).
Is the hybrid gravity system good for us?
The proposed hybrid gravity system answers many of the criticisms the Area N3 Committee raised concerning the grinder pump proposal:
• The mini lift stations will be in the public right of way. The grinder pumps would have been on our property, within 30 feet of our homes.
• The county will supply the electrical power to run the mini lift stations. The homeowners would have provided electricity for the grinder pumps.
• In the event of emergency, the county will only have to pump out 6 to 10 mini lift stations, instead of 200 individual grinder pumps.
• The homeowner will not be required to install electrical equipment. The grinder pumps would have required each homeowner to install an electrical control panel affixed to the house.
• The mini lift stations will send an electronic signal to alert the Utilities Department in the event of malfunction. The homeowner would need to call the county to report a grinder pump malfunction.
• In the event of pump failure, the mini lift stations will overflow through the manholes. In the event of grinder pump failure, sewage could back up into the home.
Even though the N-3 Committee had earlier endorsed a vacuum system (at the time, it appeared to be the only option to the grinder pumps), the hybrid gravity system offers some advantages over the vacuum system:
• No homes will be sacrificed for the hybrid gravity system. A home would have been condemned and demolished to make way for a vacuum station.
• There will be no “candy canes” in the yards with a hybrid gravity system. There would be a “candy cane” in every yard with a vacuum system.
The committee does have several concerns about the hybrid gravity system:
• The visibility of the control panels. As stated above, the County will endeavor to put the mini lift stations (and control panels) in out-of-the-way locations. However, the more lift stations that are needed, the greater the chance that some of them will be more visible. The County has indicated that they may put at least some rudimentary landscaping around the control panels; we imagine the homeowner would be free to improve on that so long as access to the panel is not impaired.
• Odor. The County states that odor should not be a problem, partly because each mini lift station will be serving a limited number of homes. (The bigger the lift station, the greater the potential for odor.) However, in the case of malfunction, odor could temporarily be a problem (although this is true of any sewer system).
As we have said before, the county is going to put us on central sewer of one sort or another. Every sewer system technology has some potential drawbacks. The committee had previously endorsed the vacuum system, despite its drawbacks (need for a vacuum station, candy canes in every yard). We believe the advantages of the hybrid gravity system outweigh the potential disadvantages.
How this came about
At the County Commission meeting of Feb. 13, 2013, where approximately 50 neighbors showed up with “Dump the Pumps” signs, the commissioners requested that the County Utilities staff take a closer look at the grinder pump proposal for our area as well as the future of the entire septic tank replacement program, since our Committee research indicated that many of the figures used to evaluate the alternative systems were out of date.
The staff retained Hazen and Sawyer Engineers, who provided the original conceptual design for the entire septic system replacement plan, to revisit the costs of grinder pumps. At your Committee’s request, the review considered additional costs for larger storage tanks, electrical outlets for generator operation, and even the cost of generators, in order to bring the grinder pump system up to the level of service provided to other County Utility customers. Using those parameters, the engineers found that the grinder pump system was closer in cost to the alternatives than had originally been shown.
While updating the cost figures, the engineering firm also introduced a new service option: the hybrid gravity system.
In the original sewer system master plan from 2000, there was no mention of hybrid gravity systems. County ordinances at the time prohibited mini lift stations. Now, the county seems willing to consider these systems for retrofits like ours.
Committee endorses hybrid gravity system
The Area N3 Committee endorses the hybrid gravity system for our area. We believe the County Utilities staff has gone the extra mile to design a system that the neighborhood will be happy with. The hybrid gravity system answers every concern we raised about the grinder pump system, and answers those concerns perhaps even better than a vacuum system would have.
What is next
In the coming weeks each affected resident in Area N3 will receive notice of a public meeting, most likely to be held at the South Gate Community Center. At this meeting, you will be able to hear for yourself about the hybrid gravity system, ask questions, and make up your own mind.
Assuming that the tone of the meeting is supportive, the County Utilities staff will then make a recommendation to the County Commission to proceed with the hybrid gravity system for Area N3. Then, at long last, construction will begin.
We urge you to attend the public meeting and to learn about the hybrid gravity proposal. We believe that the hybrid gravity system is a good solution for providing sewer service to our neighborhood, which presents many engineering challenges.
Government at work
The committee would like to thank all of the County Commissioners for welcoming us into their offices, listening to our concerns, and finally directing the staff to take a hard look at the grinder pump proposal and see if there wasn’t a better alternative.
We commend the County Utilities staff for working with us to come up with an innovative solution for our neighborhood. We have the utmost confidence in the Utilities Department to deliver us a first-rate sewer system.
We thank all the neighbors who attended the County Commission meeting of Feb. 13, 2013, waving signs and speaking against the grinder pump proposal. In the end, the demonstration of neighborhood support was essential to drive home the committee’s message and to get the Commission to act.
Finally, we thank Mike Scarborough for the countless hours he spent researching grinder pumps and other alternative sewer systems. His blog has been instrumental in providing factual information to our community, the staff and the Commissioners.
Peter Gentile (chairman and report author)
Mike Scarborough (research director)
Carol Belding (secretary)
Del Macaulay (treasurer)
Dr. Henry Abraham (vice-chairman)