HomeMy WebLinkAboutDocumentation_Workshop_Tab 03_04/29/2019WTP Backup Option Outline:
Background
The Tequesta Water Treatment Plant is currently undergoing an extensive upgrade project on the
original Filtration Plant. Much of the equipment being replaced is over 40 years old. Part of the
project required the removal of the original 210 Kilowatt Caterpillar generator from the old Filter Plant.
The old Generator functioned as a partially redundant system to the 1 MW generator that powers both
the Newer RO Plant as well as the Original Filter Plant during FPL power failures.
Demo-ed Original 210 Kilowatt generator
Why is another backup generator necessary if we have a capable generator
system already?
• Our water system operates on electricity from the grid, and water pressure to
your homes is provided by electric pumps and other electrical equipment.
o Experience has taught us that despite having the required electrical
backup required by the F.A.C. and the Florida Department of
Environmental Health & (Palm Beach County Health Department).
Extreme weather - lightning, nuisance animals, and traffic accidents can
cause — blackouts and other power fluctuations. Any of which could
overcome the design limitations of the Automatic Transfer Switch and
Switchgear. (This panel monitors the incoming power from the grid and
determines if there are problems with the grid power and when to turn
the Main Generator on).
o This process must be completed within 15 to 25 seconds for the
equipment to maintain distribution pressure to the customers.
o If generator startup takes longer than 25 seconds or if an event occurs
during the highest flow periods (which happens once or twice a given
week), it will trigger a system wide Boil Water Notice do to the system
pressure dropping below 20 psi.
What can be done to increase the reliability of the Water System and what options are
available?
Some Options are:
• Retaining the Old Generator relocated to the rear of the Old Filter Plant,
mounted and enclosed in a new shelter, integrated to the new Motor Control
Center via a new Automatic Transfer Switch
• Replacing the Old Generator with a New Genset in a trailer platform — also
integrated to the new Motor Control Center via a new Automatic Transfer Switch
• Installing a Hydro -pneumatic Tank (This option provides only a few seconds of
system pressure in the event of a power event and the Main Backup Generator
must still function and transfer power flawlessly in order to it to contribute to a
successful transfer of power with uninterrupted pressure to distribution.
• Replacing the Old Generator with a New Genset in a trailer platform — also
integrated to the new Motor Control Center via a new Automatic Transfer Switch
with the installation of Hydro -pneumatic Tank.
• Installing an Automated Control Valve at the Interconnects with Jupiter.
• Installing an Elevated Storage Tank
The Village Manager, myself, Jay Wickham, and Tom Bradford, met with the Consulting
Engineer and the Electrical Engineer to discuss the merits of each option as well as
potential combinations integrated to the system:
The most effective and simplest option would be the addition of an elevated storage tank. This
would provide water pressure to the distribution by gravity and could feed the system from 20
to 80 minutes even without electricity. Unfortunately it would be the most expensive and
visible option. (Would it be architecturally acceptable if the cost was warranted?)
Composite Elevated Tower
Automated control valve option at one, or both of the Interconnects with Tequesta and Jupiter.
If this option is viable given the Hydraulic Models of both Distribution systems, a control system
could be engineered to open a valve to provide water and pressure to our system during a
generator malfunction or some other catastrophic failure event. (This process would only be
needed for an additional few seconds to a few minutes, during the transition occurring in a
power event).
The Generator Replacement Option.
Automated Control Valve
Caterpillar 200 kW Generator
We concluded the best value with the greatest threat mitigation would be to replace
the old Filter Plant Generator with a new trailer mounted generator system coupled to a
new Automatic Transfer Switch.
Where are we now?
We have requested specs and cost estimates to implement a change order for the installation of an
Automatic Transfer Switch in the new Motor Control Center. This will provide the connections
necessary to power the original Filter Plant and High Service pumps 1 through 4 if there is a
catastrophic failure to the Main Generator or Electrical Switch Gear. The Generator options and
configurations can be determined at a later time after the change order is implemented.
This is a time sensitive decision we need to make — in regards to taking advantage of the Renewal
Project that is ongoing. If the council makes a decision to move forward with replacing the secondary
generator, change orders to the current contract could be incorporated easily to the project.
Questions from the Council...