Drainage Inlets

Information listed below is from the FDOT Roadway Design Standards (2012 edition). Short & long wall data is for the largest recommended inside diameter (ID) RCP size. U.S. Foundry steel grate item numbers are for AASHTO H-20 wheel loads, and pedestrian (non-traffic) loading.

Traffic Bearing Inlets

Inside dimensions are the same for both cast-in-place and pre-cast, except for inlet types J, S, & V which all have pre-cast inside dimensions of 3′–3″ × 3′–10″.
Alt. B structure bottom (FDOT index 200) may be used with inlet types F, G, J, S, & V.
Do *not* use type J inlet where bicycle traffic is anticipated.
Type S inlet is for shoulder gutter applications.
Inlet Type	FDOT Index	CIP Outside Dimensions	PC Outside Dimensions	Inside Dimensions	Short Wall ID	Long Wall ID	H-20 Grate	Non-Traf Grate
F	233	3′–10″ × 5′–4″	3′–6″ × 5′–0″	2′–6″ × 4′–0″	18″	30″	6631	6630
G	233	6′–2″ × 6′–4″	6′–2″ × 6′–4″	4′–10″ × 5′–0″	42″	42″	6661	6660
J	234	4′–3″ × 5′–4″	4′–3″ × 4′–10″	2′–11″ × 4′–0″	24″	30″	6685	6652
S	220	4′–3″ × 5′–4″	4′–3″ × 4′–10″	2′–11″ × 4′–0″	24″	30″	6658	6652
V	221	4′–3″ × 5′–4″	4′–3″ × 4′–10″	2′–11″ × 4′–0″	24″	30″	6657	6651

Non-Traffic Bearing Inlets

Inside dimensions are the same for both cast-in-place and pre-cast.
Alt. B structure bottom (FDOT index 200) may be used with inlet types C, D, & E.
H(2) is type H inlet with 2 steel grates; H(4) is type H inlet with 4 steel grates.
**Note:** Although H-20 steel grate item numbers are listed for non-traffic bearing inlets, the use of these inlets in areas subject to heavy wheel loads is strongly discouraged.
Inlet Type	FDOT Index	CIP Outside Dimensions	PC Outside Dimensions	Inside Dimensions	Short Wall ID	Long Wall ID	H-20 Grate	Non-Traf Grate
C	232	3′–4″ × 4′–5″	3′–0″ × 4′–1″	2′–0″ × 3′–1″	18″	24″	6611	6606
D	232	4′–5″ × 5′–5″	4′–1″ × 5′–1″	3′–1″ × 4′–1″	24″	36″	6626	6607
E	232	4′–4″ × 5′–10″	4′–0″ × 5′–6″	3′–0″ × 4′–6″	24″	36″	6616	6608
H(2)	232	4′–4″ × 7′–11″	4′–0″ × 7′–7″	3′–0″ × 6′–7″	24″	60″ or 2–24″	6621	6609
H(4)	232	4′–4″ × 10′–1″	4′–0″ × 9′–9″	3′–0″ × 8′–9″	24″	78″ or 2–30″	?	?