Forest Hills Watershed Detention Project - Phase 1

To: Forest Hills Drive/Pond Area Residents
From: Jon Lutz, P.E.
Date: 12/09/2019
Subject: Forest Hills Drainage Improvements
IIW Project No.: 19098

Project Status:

1. IIW has completed approximately 80% of the preliminary study and design for the channel, pond and spillway. The concept follows previously submitted plans, increasing the principal and emergency spillway capacity and adding sediment forebay.

2. Pond sediment removal is scheduled for late winter so that equipment can operate on frozen ground. The pond must be drained in order for the bottom sediment to freeze. A contractor is scheduled to excavate a channel through the embankment and drain the water beginning Thursday, December 12th. Please refrain from entering onto the pond bottom and breach area during and after draining. Iowa DNR indicated the taking of remnant fish by means other than fishing line and hook would be unlawful. A safety fence will be installed around the breach area.

3. Final construction plans are underway with anticipated bidding in early February. Sediment removal is scheduled to begin in late winter with spillway construction to follow. Construction of the pipe from