03
Jun
The high water levels have heightened awareness of the air gaps for all LMR Bridges between New Orleans and Baton Rouge.
There have been some conflicts regarding which numbers should be used.
Research has shown up to 4 different bridge measurement references from the:
- USCG
- NOAA PORTS
- 2015 USACE Map Books
- NOBRA Pilots Bridge Card
Recently NOAA conducted a complete survey of the LMR from Baton Rouge to SWP.
New measurements were taken during those surveys. Accurate air gap numbers should be available once the measurements and the datum numbers are computed.
Also, efforts are underway to have air gap sensors installed on all bridges.
But, until any new measurements are provided, currently the NOBRA’s Pilot Card provides the pilots with their best assumption of the safest measurements that have worked for them.
Accordingly, LAMA’s air gap computations will now reference those numbers.
I have provided a table that shows the change in the calculations.
Additionally, the NOBRA Bridge Card is attached.
| Bridge Name |
Mississippi River Mile |
Was |
Now |
Referenced River Guage |
|||
|
Baton Rouge HWY Bridge |
229.3 |
174.0 |
172.5 |
Baton Rouge |
|||
|
Interstate Route10 |
|||||||
|
Ascension • St. James HWY Bridge |
167.4 |
171.0 |
168.0 |
Donaldsonvile |
|||
|
Sunshine Bridge |
|||||||
|
_ |
|||||||
|
Gramercy Bridge |
145.9 |
164.0 |
164.9 |
Reserve |
|||
|
Hale Bogs Bridge |
121.6 |
158.0 |
158.4 |
Reserve |
|||
|
Interstate Route 310 |
|||||||
|
|
|
||||||
|
Huey P. Long RR and HWY Bridge |
106.1 |
152.3 | 153.8 |
Carrollton |
|||
|
Crescent City Connection Bridges |
95.7 & 95.8 |
171.0 |
170.0 |
Carrollton | |||
