Lee's Summit

A Floodplain Development Permit application is being transmitted separately for the low-water crossing. Please return the completed and signed/sealed form, along with the relevant design sheets for the low-water crossing in one (1) pdf file.

Sheet 7: It appears silt fence is the only method to contain sediment migration within the cut/fill area. We had discussed the possibility of constructing sediment basins/traps at key locations to eliminate this concern, but I did not see anything other than silt fence. Many locations of the silt fence are shown along the centerline of swales, which will not work very effectively. Please analyze, and determine if other measures are needed such as a temporary sediment basin or temporary sediment trap.

Locations of concern in regard to the above comment include: 1) the northeast corner of the site, and 2) the northwest corner of the site. Each of these locations appear to be well-suited for placement of a temporary sediment basin or trap.

If either of these features are selected for the project (i.e., sediment basin or sediment trap), a complete design is required. Although standard KCAPWA details can be used, a site-specific design is also required to augment the standard details.

Sheet 3 includes notation about a conspan bridge. Why was this included on the plans? It is our understanding that the bridge will not be built until such time that coordination between the City and the developer on the floodway study has been completed. This was discussed in detail with the previous engineer, Brian Glenn of Phoenix Engineering.

A low water crossing is shown on Sheet 4. This is located within the regulatory floodway. If utilizing a low water crossing within the regulatory floodway, a no-rise certificate, accompanied by sufficient modeling would be required.

Exact locations of the regulatory floodplain fringe, the regulatory floodway, and elevations of same shall be provided. None of these elements were shown on the plans.

A USACE permit is likely required. Line 12 of the floodplain permit application appears to be missing this information.

An MDNR land disturbance permit is required.

Line 11 of the Floodplain Permit application appears to be missing the flood panel number.

Lines 9 of 10 of the Floodplain Development Permit application appears to be missing definitive numbers for the BFE. The City does not allow a range of values, but rather, a single number. In this case, it would appear the most conservative figure should be utilized.

The basin shown in the southeast portion of the project was not labeled. Is this a basin for 40 hour extended detention? If so, please label.

Will the water quality basin(?) described in the above comment incorporate any temporary erosion and sediment control devices such as a skimmer? If not, why?

It is our understanding that a CLOMR-F shall be obtained for all lots currently partially or wholly-within the regulatory floodplain prior to approval of any plat. Has this process been started? This should probably be initiated at this time.

Recommend a meeting be setup between the engineer and the City to discuss these complicated issues in regard to the floodplain, the floodway, the CLOMR-F, the coordination between the City and the developer concerning the new bridge, and all other items associated with this application.