Rainbow Dam is a high-hazard, 2,000-ft-long by 42-ft-high earthen embankment flood-control dam bounded immediately upstream by a public school campus and downstream by a public park and large neighborhood. The auxiliary spillway did not have adequate hydraulic capacity during the freeboard hydrograph event, and the dam’s internal drainage system did not meet dam safety requirements….
Following the inception of Vermont’s Three-Acre Stormwater Rule, schools throughout Vermont needed to adapt their campuses to manage stormwater in accordance with Vermont Stormwater General Permit 3-9050. To help schools successfully manage these challenges, D&K has provided engineering and environmental services for feasibility studies and the design of stormwater improvements for five schools. The projects…
Located on the Otter Creek, the Huntington Falls Hydroelectric Project is a historic facility that required redevelopment. The D&K team assessed the two non-operational turbines and related appurtenances, the trash rack, and raker upgrades to the Unit 3 turbine following FERC relicensing. Additional D&K services included design and coordination to upgrade all three turbines, resulting…
The Neshobe River crosses through the heart of downtown Brandon, and the historic stone masonry bridge carrying Central Street/US 7 and numerous utilities had a history of substantially inadequate hydraulic capacity. As a demonstration of this issue, the town opened the front and rear doors of the adjacent town offices during a large storm event…
Heavy rainfall and substantial snowmelt from a storm event combined with insufficient drainage systems to wash out 2,800 LF of a vital roadway crossing a mountain. The steep and winding road serves approximately 1,400 vehicles per day and connects VT 100 and VT 12. The Town of Rochester applied for and received FHWA-ER funding to…
Two dams in a park owned by a community association were damaged by storm flows. The lower dam was breached and required design alternatives for its removal; the upper dam had to be evaluated for repairs. D&K reviewed the structural elements of both dams, the retaining wall, and the stream character upstream and downstream. Our…
Framed by a public park and a residential area and carrying a city street, Robin Hood Dam was reclassified by the State of New Hampshire as a high-hazard dam, and its spillway did not have the capacity to meet New Hampshire Dam Safety requirements. The City of Keene engaged D&K to evaluate the dam, develop…
The Upper Wilson Pond Dam is a small, high-hazard, earth embankment dam impounding a recreation pond. Recently found to be in poor condition, the dam is owned by the Town of Swanzey, and the pond is bounded by homes and properties located within the City of Keene. D&K’s project team completed a study that evaluated…
Storm flows from Jewell Brook in Ludlow are controlled by flood control dams (numbered 1, 2, 3, and 5) located in a rural, hilly, largely forested area. Previous evaluations of this system indicated that Site 1 had the potential for overtopping and the spillway design hydrograph would exceed allowable stresses at three of the system’s…