Hoyle Tanner completed the preliminary engineering study to upgrade the South Woodstock WWTF. The original WWTF was a 50,000 gpd package conventional activated sludge facility that had not been upgraded since 1966. Redundancy was not provided for process tankage including the aeration basin and secondary clarifier. Therefore, the process units could not be taken offline for tank inspection or repair. The facility is now required to nitrify and denitrify with an effluent Total Nitrogen (TN) limit in the NPDES permit. Additionally, a portion of the WWTF site is in the Regulatory Floodway, creating significant limitations on siting new process tankage.
For the upgrade of the WWTF, three process alternatives were considered: Sequencing Batch Reactor (SBR), Membrane Bioreactor (MBR), and submerged attached growth bioreactor (SAGB). The alternatives were evaluated based on a life-cycle cost analysis and non-monetary factors. The recommended alternative was an SBR process with an innovative equipment layout, allowing all process equipment to be accessed from above the water line. This allowed for a two-tank SBR process without pre-equalization to meet the Vermont DEC SBR design guidelines. This innovative approach saved capital cost while realizing a lower life-cycle cost, as well. The new facility was constructed and put into service prior to decommissioning the original facility. Construction of the new SBR facility was completed in 2023.
SERVICES
Study
Alternatives Development & Analysis
Preliminary Design
Permitting
Funding Assistance
Public Outreach
Final Design
Bid Process Administration
Construction Administration
From the blog
Learn about ongoing projects and the innovative processes we employ for our clients.
We are excited to announce that Structural Engineer Katie Welch has been appointed Director at Large for the Structural Engineers of New Hampshire (SENH) Board of Directors. The SENH...
At Hoyle Tanner, we have been deeply involved in the planning and design phases of the Millinocket Municipal Airport project. This project is a significant part of the town's...
Project Overview Hoyle Tanner is providing environmental engineering design and construction services for the Brighton Wastewater Treatment Facility (WWTF) upgrade. The Brighton WWTF operates a small lagoon system with...
Our team has been hard at work load rating bridges across Massachusetts. In simple terms, a load rating is an evaluation of a bridge to determine its capacity to...
What drew you to Hoyle Tanner? When I first started looking for an internship, I honestly had no idea what I was looking for. I applied to the Construction...
One of the most important, challenging, and rewarding aspects of the civil engineering curriculum at a college or university is the senior capstone project, or senior project. A “culminating...
What drew you to Hoyle Tanner? As a student who hasn’t decided on a career path, I value the different divisions that Hoyle Tanner has to offer. I figured...
Meet Eric Doe, PE – Wastewater Engineer & DIYer What drew you to Hoyle Tanner? It was a combination of factors that ultimately had me accept a job offer...
Airports have access to a wide range of funding options—but navigating these opportunities can be complex. Hoyle Tanner helps airports strategically plan, prioritize, and secure the funding they need...