Hoyle Tanner prepared a hydrologic and hydraulic study for the replacement of a structurally deficient corrugated metal pipe (CMP) and reinforced concrete pipe.
The existing crossing is comprised of two adjacent culverts. The west culvert is a 4’ diameter reinforced concrete pipe and the east culvert is a 3’ diameter CMP. Due to its deteriorated condition and history of flooding in this area the Town of Derry is investigating replacement options for these culverts.
Hoyle Tanner performed hydrologic and hydraulic analysis and evaluated the existing opening of the culvert and recommended a new culvert type and opening that passes the 50-year flood event with a minimum of 1′ of freeboard per New Hampshire Department of Transportation (NHDOT) requirements. The recommended structure type will be 30’ in span. The project was fully funded through Town funds.
SERVICES
Hydraulic Analysis
Study
Final Design
Bid Process Administration
Construction Administration
From the blog
Learn about ongoing projects and the innovative processes we employ for our clients.
Hoyle Tanner is excited to welcome Evan Raymond, PE, to our Ground Transportation Division as a Senior Transportation Engineer. Based in our Yarmouth, Maine office, Evan brings nearly a decade of experience delivering roadway and multimodal transportation projects across northern New England.
We are pleased to recognize our employees celebrating work anniversaries this month. Collectively, these individuals have contributed 109 years of service to Hoyle Tanner, demonstrating the dedication and commitment that drive our continued success. We thank them for their valuable contributions and congratulate them on their anniversaries!
Joshua Sklarsky joins Hoyle Tanner as the firm’s first Chief Technology Officer, bringing over 15 years of experience in technology leadership and innovation. Known for translating complex ideas into practical strategies, he will help drive digital transformation and strengthen the firm’s technology initiatives. His leadership comes at an exciting time of growth and investment in advanced technologies.
Drought is often understood as a period with too little rain, but its impacts extend far beyond dry landscapes. Drought status influences drinking water supplies, groundwater availability, infrastructure performance,...
Hoyle Tanner’s Maplewood Avenue Bridge Rehabilitation Project in Portsmouth, NH earned a Silver Engineering Excellence Award for its innovative approach to restoring and preserving the historic 1896 bridge.
At Hoyle Tanner, our strength starts with our people. Each year, our leadership team takes the opportunity to recognize individuals who are not only delivering great work for our...
Mountain condo community across the river from Loon Ski Resort upgrades drainage, roadways and landscaping. Hoyle Tanner is providing civil engineering design, permitting and construction administration services for a...
Across New England, interest in trail and active transportation projects continues to grow. Communities see the benefits clearly – improved connectivity, safer travel options, and more vibrant public spaces....
