Drainage Systems Inspection Flashcards
6 cards from real CTQP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Drainage Systems Inspection flashcards as text
What is a 'retention pond' vs. a 'detention pond' in FDOT stormwater management?
Answer: Retention ponds store water permanently; detention ponds temporarily hold water and release it slowly
Retention ponds (wet ponds) permanently store a water pool and treat runoff by sedimentation; detention ponds (dry ponds) temporarily hold stormwater during storms and release it slowly after the event.
What does 'flap gate' or 'tide gate' do in a drainage outfall?
Answer: Prevents backflow from a receiving water body into the drainage system
A flap gate or tide gate is a one-way valve installed at a drainage outfall to allow stormwater to discharge freely while preventing backflow from tidal or high water in the receiving body.
What is the inspector's responsibility during pipe trench backfill operations?
Answer: To verify compaction lifts, material, and density testing around and over the pipe
The inspector must verify that backfill is placed in proper lift thicknesses, using approved materials, and compacted to specified densities both beside and over the pipe to prevent settlement and pipe damage.
What is the significance of the 'invert elevation' of a storm drain pipe?
Answer: The elevation of the bottom inside of the pipe, which controls flow direction and capacity
The invert elevation is the inside bottom of the pipe and controls the slope, flow direction, and hydraulic performance of the drainage system; it must match design plans precisely.
What material is most commonly specified for drainage pipe in FDOT projects where a corrosive environment is a concern?
Answer: Reinforced concrete pipe (RCP) or high-density polyethylene (HDPE)
In corrosive environments (acidic soils, salt water), FDOT typically specifies reinforced concrete pipe (RCP) or HDPE pipe rather than corrugated metal, which is susceptible to corrosion.
What action must an inspector take before a drainage pipe is buried if the pipe appears cracked or damaged?
Answer: Reject the damaged pipe and require replacement with conforming material before backfilling
Damaged or cracked pipe must be rejected before burial; once a defective pipe is buried it is extremely costly to repair, so rejection before backfilling is essential.