ShawneeDispatch.com

The Public Works and Safety Committee Tuesday was scheduled to discuss allowing two new subdivisions along Clear Creek pay a fee rather than provide stormwater detention facilities.

Stormwater drainage has been a big item of discussion in Shawnee, with the city recently implementing a storm water utility to help fund costs of maintaining its stormwater system. But city officials say that a storm drainage analysis for the planned single-family subdivisions The Village at Clear Creek and The Estates at Clear Creek, both located between Mize and Clare roads north of 71st Street, shows that on-site storm water detention could actually make downstream flooding a little bit worse rather than preventing it.

The two neighboring subdivisions are planned to take up a 85-acre tract of land, with Clear Creek running north-south through the middle. The combined number of homes planned for the two neighborhoods is 110.

The city approved development of The Village at Clear Creek, planned for the eastern 60 acres, with the requirement of having on-site storm water detention because it was a residential development greater than 20 acres. The Estates at Clear Creek, proposed for the western 25 acres, has yet to be considered by the Shawnee Planning Commission.

But if a development is discharging stormwater directly into the 100-year floodplain, the city engineer can permit a fee payment in lieu of on-site stormwater detention.

Doug Wesselschmidt, city engineer, said the developer's engineer determined that if both of the subdivisions did not provide on-site storm water detention, the 100-year storm water surface elevation would rise .01 feet, about 1/8 an inch. If they did provide detention facilities, the 100-year storm water surface elevation would rise .05 feet, about half an inch.

Wesselschmidt noted that the site for the developments is in the lower third of the creek's watershed area. If the storm water is retained in a detention facility, which slowly releases water back into the creek, the additional storm water from upstream could reach the area just as the detention facility releases the water, increasing flooding potential.