Myth: Thirsty Duck BFD's discharge more volume during a storm then a traditional outfall structure.
Fact: Total volume discharged is the same for both a system with a Thirsty Duck BFD and a system with a traditional outfall structure. In all stormwater applications, total discharge is simply the total runoff to the pond, minus any retention requirements for water quality or flood abatement purposes.
Myth: If everyone has a Thirsty Duck BFD, the outfall capacity will be exceeded.
Fact: Notwithstanding minor differences in the time of concentration between locations, traditional outfall structures are all discharging the peak rate at approximately the same time i.e. if your pond is full and discharging the peak rate, your neighbor's pond is full and discharging the peak rate too.
Myth: Thirsty Duck BFD's are more prone to clogging then traditional outfall structures.
Fact: Thirsty Duck TD Series BFD's have been installed and operating successfully since 2004 without any incidents. By design, both ER and TD Series are self skimming since a portion of the float is always submerged.
Myth: I can get the same result by using a long weir.
Fact: Long weirs may be able to discharge the peak rate at lower heads, however they also exceed the peak discharge at lower heads. Thirsty Duck BFD's maintain the peak discharge rate, regardless of head.
Myth: Thirsty Duck cannot be used where multiple storm event analysis is required
Fact: There are multiple ways to use a Thirsty Duck BFD to comply with multiple storm event criteria...
- Pair a Thirsty Duck BFD with a traditional fixed weir or orifice.
- Use multiple Thirsty Duck BFD's at varying elevations.
- A single restriction ER Series BFD can be designed with multiple stages.
Myth: Thirsty Duck BFD's are "operable" devices.
Fact: Thirsty Duck BFD's are passively operated, since buoyancy does all the work, and no human interaction is required.
Myth: It will take me longer to permit a Thirsty Duck BFD than a traditional outfall structure.
Fact: The most recent permit for a Thirsty Duck BFD was issued by the Southwest Florida Water Management District in only 43 Days. See the letter from the engineer of record here.