Tribal Transportation Department Flood Damage Assessment

May, 2016

Over the weekend days of May 6, 7, 8, 2016, the Mill Creek Drainage on the Wind River Reservation experienced record high rainfall. On Monday morning, recognizing that flood damage had likely occurred, James Gores and Associates made contact with the Tribal Transportation Department to offer our assistance in assessing damages. The Tribal Transportation Director called back at 8:30a.m.; by 9:30, we were on site, evaluating the bridges that were damaged and, in some cases, overtopped. Damage assessments and inventory was made on six bridges, four culverts, and a section of the reservation’s main thoroughfare that had suffered damage.

The Tribal Transportation Department asked us to prepare a damage repair cost estimate so that they could apply for reimbursement of the expenses that they were facing for repair of the damage that occurred in their road system. Our staff, guided by Reservation Transportation managers, inventoried system damages over the course of the next two days. In one case, a culvert sustained a piping failure due to the faulty installation of the culvert. The soils surrounding the culvert were carried away. An unsuspecting motorist had driven off into the resulting cavern. Similar evidence was photographed and described with the estimated costs to accompany the needed repairs.

Within four days, we had assembled detailed cost estimates of the incurred damage and delivered the report to the Tribal Transportation Department. The Department was able to achieve their objective of having a defensible basis for requesting reimbursement from the reservation roads through BIA to accomplish the repairs. The total road system damage amounted to over $500,000.

We provided recommendations to the department regarding repair techniques that would give both short-term results and long term preemptive protections needed in the event that an even larger flood event should on happen in early June when snowmelt runoff would peak. The Department accomplished the repairs with their own forces, and had the road system fully repaired and back fully safe condition within the remaining three weeks of May.