Provide construction grade plans/details showing the existing curb system is structurally adequate and is in compliance with the code in effect at the time of installation. If the details are reviewed and accepted by this office as meeting those requirements. The unit can be replaced in kind
If it is questionable that the original curb installation was in compliance with the code in effect at that time,then an engineer's evaluation and recommendations for remedial measures will be required
Engineered details in compliance w/Chapter 15 of the 2017 6th Edition FBC-B is always an acceptable option for compliance