Low Water Crossings and Bridge Demolition, Maquoketa Caves State Park, Jackson County

The Iowa Department of Natural Resources is requesting competitive quotations for low water crossings and bridge demolition at Maquoketa Caves State Park in Jackson County, with bids due electronically by July 23, 2026 at 3:00 p.m. This is a unit-price minor public improvement contract with a September 30, 2026 completion deadline.

The scope encompasses removal of a deteriorated wooden bridge, stairs, posts, and railroad ties; installation of two low water crossings using prefabricated concrete (PCC) hog slats (nine 4-foot by 10-foot slats per crossing, Hog Slat, Inc. Item #1230 or approved equal); placement of 32 tons of granular subbase material; minor trail grading and realignment; and site restoration with dense shade erosion control seeding. Contractors are required to visit and inspect the site prior to bidding and must verify all dimensions and conditions shown on the plans, notifying the DNR Engineer of any discrepancies. Contractors bear responsibility for obtaining their own waste disposal areas, maintaining surface drainage on graded areas, and providing daily erosion control materials and labor. Storage, parking, and service areas require DNR Engineer approval, and no disturbance of vegetation outside construction limits is permitted.

Contractors with contract amounts exceeding $25,000 must provide a performance bond equal to 100 percent of the contract price and maintain public liability insurance with minimum coverage of $250,000 per person and $500,000 per occurrence. All contractors must obtain an NPDES Stormwater Discharge Permit and be registered with the Iowa Department of Revenue. Payment is made on a unit-price basis within 30 days of approved invoices; the Department retains the right to withhold up to 3 percent of payment. Liquidated damages are assessed at $100 per calendar day for work uncompleted after September 30, 2026. A one-year warranty period follows final acceptance. Contact Darin Galbraith at 515-344-0055 for procurement questions and Michael Dufoe, P.E., at 515-985-9196 for technical inquiries.