CO NP ROMO 407(1) Holzwarth Culvert

The Federal Highway Administration seeks replacement of the deficient Holzwarth Culvert with a new steel girder bridge in Rocky Mountain National Park near Grand Lake, Colorado, with proposals due October 27, 2026. Amendment A001, effective October 19, 2026, extended the deadline one week and clarified critical constraints: no ground-disturbing activities or equipment mobilization may commence before August 2, 2027, though material delivery, fabrication, surveying, mobilization, and traffic control may proceed earlier.

Place of performance is Grand Lake, Colorado (approximately nine miles north of Grand Lake along US Highway 34 at 8,900 feet elevation). The existing six-barrel corrugated metal arch pipe culvert (Structure No. 1520-029S) conveys Colorado River flow and provides access to the Holzwarth Historic Site, employee housing, and National Park Service and Forest Service recreation facilities. The 2024 Federal Highway Administration inspection rated the culvert Priority B (Major), with severe corrosion, widespread barrel distortion, concrete headwall delamination, undermining up to 2.5 feet, and 50 percent reduced load ratings (inventory 29 tons, operating 38 tons).

Scope includes removal of the existing culvert, construction of a new 10-foot-wide by 48-foot-long prefabricated modular steel vehicular bridge with cast-in-place concrete deck, new abutments with 8.68-inch-diameter micropiles (180 linear feet), temporary stream diversion with riprap, 120 tons of aggregate roadway surfacing, electrical line relocation, and relocation of historic head gates to a new concrete slab. The Holzwarth Culvert Access Road is approximately 13 feet wide with tight turns; temporary widening is required to prevent truck off-tracking onto sensitive environmental resources. Construction access is restricted to within 100 feet west of the bridge. Streambed work is prohibited when Colorado River flow exceeds 50 cubic feet per second, and night and weekend work are prohibited. A mandatory preconstruction conference must occur seven days before work begins; performance bonds are due within 10 calendar days of award.

NAICS code is 237310 (Highway, Street, and Bridge Construction); PSC code is Y1LB. Amendment A001 clarified that solicitation number 6982AF27B000004 must appear on bid bonds and all submission documents.