DEQ seeks comment on draft 401 water quality certification for Allumbaugh Street bridge replacement

Accepting comments from December 11, 2024, through January 1, 2025.

BOISE – The Idaho Department of Environmental Quality (DEQ) is seeking comment on a draft water quality certification for the Allumbaugh Street bridge replacement project.

This project proposes to replace the existing Allumbaugh Street bridge over Ridenbaugh Canal with a new bridge, which includes additional southbound travel lanes, and improved bicycle and pedestrian facilities. The new bridge will feature a concrete lined channel to mitigate scour and is a voided slab, spanning 43 feet in length and 68 feet in width. Concrete walls and abutments will be placed on each side of the bridge. Two feet of riprap will be placed along the canal side slopes, and the canal will be lined with six inches of concrete over 4 inches of crushed aggregate to prevent canal scour and erosion, along with geotextile fabric. An estimated total of 300 linear feet (LF) of the Ridenbaugh Canal will be impacted. A site-specific Stormwater Pollution Prevention Plan (SWPPP) will be prepared and implemented for construction activities. 

Based upon review of the federal ​permit​ application, readily available water quality related materials, and certification request in accordance with 40 C.F.R. §§ 121.5 (b) and (c) and 121.7 (c), DEQ, certifies that if the permittee complies with the terms and conditions imposed by the federal ​permit​ and the conditions set forth in this water quality certification, then it is reasonable for DEQ to conclude that the activity will comply with water quality requirements, including applicable requirements of the Clean Water Act §§ 301, 302, 303, 306, and 307, Idaho’s “Water Quality Standards” (IDAPA 58.01.02), and other appropriate water quality requirements of state law.  

The draft certification is available for review on DEQ’s Public Comment Opportunities web page. Written comments will be accepted through January 1, 2025, at 5 p.m. Mountain Time. Submit comments electronically using the form below or by mail or email to:  

Meghan Cline
1445 N Orchard St.
Boise, ID 83706
meghan.cline@deq.idaho.gov

Related Documents

Draft Certifications

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