Drainage pipes would serve the initial purpose, but they would need to be of a diameter such as to equal the cross section of the canal in capacity. The canals measure roughly 14 by 50 feet, which translates to a pretty big pipe. At that point, a canal is less expensive to construct and offers a benefit/liability that pipes do not, unlimited capacity, if you are willing to overfill the canal.
This can and did cut both ways in the pre-dawn hours prior to Katrina's arrival, with certain areas pumped dry(er) while the receiving canal overfilled and lightly flooded other areas.
NO levee related story....
http://www.wdsu.com/news/5055164/detail.html
SOUTHPORT, Fla. -- A construction company based in the Florida Panhandle has denied allegations in a federal lawsuit that it was partly to blame for the failure of a New Orleans levee after Hurricane Katrina.
Daniel Becnel Jr., a Reserve lawyer, sued Gulf Group Inc. of Southport, a Panama City suburb, in New Orleans last week. He claims vehicles and heavy equipment the company left on the 17th Street Canal levee contributed to its failure. Gulf Group was building a bridge near the levee.
jeffers, good call.
Plus drainage pipes need to be cleaned from time to time. Surface draining is much less expensive.