US Army 6/24/10: Sediment Cleanup on Lake Cochituate. Cleanup activities started on Lake Cochituate and continue into the summer for approximately 8 weeks, up to 6 days per week during daylight hours. Activities will include site preparation, mobilization, silt curtain installation, dredging, dewatering, water treatment, backfilling, monitoring, and site restoration. During the cleanup, boating access to and fishing within Pegan Cove will be restricted.