Levee - Routine Inspection (annual inspection)

The Public Works Department received the official findings of the US Army Corps of Engineers (USACE) routine inspection of the Kansas River Levee (Lawrence Unit) that was conducted on August 26, 2013.  Based on the findings of the inspection the Lawrence Unit received a maintenance rating of MINIMALLY ACCEPTABLE. These routine inspections have been performed annually for the last thirty years.

It should be noted that there are three possible ratings assigned for levee inspections:  UNACCEPTABLE, MINIMALLY ACCEPTABLE, and ACCEPTABLE. A maintenance rating of ACCEPTABLE or MINIMALLY ACCEPTABLE is required for eligibility in the Public Law 84-99 (P.L. 84-99) levee rehabilitation program.  Since the Lawrence Unit has received a MINIMALLY ACCEPTABLE rating, it is eligible for federal repair assistance if damaged by flooding and other program requirements are met.  However, damages due to existing deficiencies are not eligible for federal assistance.  A recent survey of the National Levee Database revealed 215 levees within a 150 mile radius of Lawrence.  The breakdown for those levees was as follows:

UNACCEPTABLE	MINIMALLY ACCEPTABLE	ACCEPTABLE	NOT RATED
5	136	13	61

Table 1 of the routine inspection report noted the following categories as unacceptable deficiencies: rock slope protection (riprap), levee embankment encroachments, unwanted vegetated growth, discharge pipes and erosion.

The riprap is the original rock slope protection and it is beginning to show signs of degradation and needs to be replaced.  Freeze thaw cycles over the years have been the major factor in the ripraps degradation. Riprap replacement will begin in the year 2014, however due to the high cost of replacing the volume of riprap required it will be done over a period of time.  The sections of the levee which are subject to greater river flow velocities and wave impacts will be addressed first.  The USACE has approved this approach to address this deficiency.

Levee embankment encroachments include a power pole set too close in proximity to the levee, an unauthorized ditch and railroad fill placed in the sandbag gaps.  Remedies for these deficiencies include relocating the power pole and removing the unauthorized ditch.  Documentation from the railroad will be requested to confirm the use of proper backfill with the railroad right of way.  If no such documentation can be provided then the emergency action plan for this location will be revised which will require monitoring of underseepage or through seepage during flooding events.

The areas of vegetative overgrowth have already been cleared and thus remedied.  With regards to the discharge pipes video inspection recordings will be submitted to the USACE for review.

The final point of concern entails the perceived degradation of the streambed on Mud Creek north of the airport.  The streambed appears to be head cutting (the elevation of the flow line of the creek is getting lower) and if left unchecked has the potential to affect the Mud Creek Levee Unit.  Additional surveying will be done along the streambed and compared to a similar survey completed during the levee certification process in 2009. 

Although the levee is in good condition it is important to address the points of concern to remain eligible for federal funds in the event of a flood event and subsequent levee damage.