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East Hidden Hills Road Caswell Creek Road Maintenance Notice of Application for State Water Quality Certification

Notice of Application for State Water Quality Certification

PN Reference Number: POA-2023-00148 v1.0
Waterway: Caswell Creek

Any applicant for a federal license or permit to conduct an activity that might result in a discharge into navigable waters, in accordance with Section 401 of the Clean Water Act (CWA) of 1977 (PL95-217), also must apply for and obtain certification from the Alaska Department of Environmental Conservation that the discharge will comply with the CWA, the Alaska Water Quality Standards, and other applicable State laws. 

Notice is hereby given that a request for a CWA §401 Water Quality Certification of a Department of the Army Permit application, Corps of Engineers’ PN Reference Number indicated above has been received for the discharge of dredged and/or fill materials into waters of the United States (WOUS), including wetlands, as described below, and shown on the project figures/drawings. The public notice and related project figures/drawings are accessible from the DEC website at https://dec.alaska.gov/water/wastewater/.

To comment on the project or request for a public hearing with respect to water quality, submit comments electronically via the DEC public notice site at https://water.alaskadec.commentinput.com?id=rmUFaMC45 on or before the public notice expiration date listed above.

Applicant:  
Matanuska Susitna Borough, Cole Branham, 350 E Dahlia Ave Palmer, AK 99645; 907-861-7801; cole.branham@matsugov.us.

Agent:  
DOWL, Joshua Grabel, 5015 Business Park Blvd., Suite 4000 Anchorage, AK 99503; 907-865-1258; jgrabel@dowl.com

Project Name:  
East Hidden Hills Road Maintenance

Location:  
The proposed activity is located within Section 20, 21, 22, 23, T. 22 North, R. 4 West; Seward Meridian; in Matanuska-Susitna Borough, Alaska. Project Site (Latitude, Longitude):  61.98933, -149.97887. With potential discharge location to an unnamed Tributary to Caswell Creek -149.978962, 61.989321; Wetlands adjacent to Caswell Creek. 

Purpose: 
The purpose of the Hidden Hills improvements is to reconstruct the roadway to collector road standards from the Parks Highway to South Caswell Loop Road.

Project Description: 
Improvements to Hidden Hills Road would include:
• Paving
• Improving the road subgrade and widening lanes-Includes minor expansion into wetlands at the toe of slope in several locations.
• Replace, repair, or install roadside hardware
• Drainage improvements
• Adjust or relocate utilities
• Clear vegetation
• Culvert Replacement includes replacing two culverts at an unnamed tributary to Caswell Creek with an 8-foot box culvert and armoring the stream channel downstream. A temporary diversion culvert would be placed during construction to maintain stream connectivity.

The project will permanently discharge up to 3,609 cubic yards of fill material into 1.1 acres of waters of the U.S., including wetlands, and temporarily discharge up to 441 cubic yards of fill material into 0.1-acre of waters of the U.S., including wetlands to make improvements to Hidden Hills Road. 

A total of 3,313 cubic yards of Type B or better fill material would be discharged into wetlands to improve the road subgrade and widen lanes, replace, repair, or install roadside hardware, adjust, or relocate utilities, and make drainage improvements. 

Up to 296 cubic yards of stream substrate fill would be permanently placed below the ordinary high-water mark (OHW) of an unnamed tributary to Caswell Creek to replace the existing culverts with an eight-foot box culvert and armor the downstream channel. Up to 441 cubic yards of gravel fill would be temporarily discharged below the OHW to install a temporary culvert to maintain stream connectivity during construction. 

Additional Information: The proposed project would require a temporary water use authorization from the State of Alaska Department of Natural Resources, as well as a Fish Habitat Permit from the Alaska Department of Fish and Game (ADF&G). 

Applicant Proposed Mitigation: The applicant proposes the following mitigation measures to avoid, minimize, and compensate for impacts to waters of the U.S., including wetlands, from activities involving discharges of fill material. 
a. Avoidance: Complete avoidance of waters of the U.S. is not possible due to meeting the project purpose of reconstructing the roadway to collector road standards. Hidden Hills Road is existing and crosses several large wetland areas and anadromous streams. 
b. Minimization: Impacts to waters of the U.S., including wetlands would be minimized by the following: 
• The Diversion channel would be filled with native material.
• Disturbed areas would be stabilized post construction.
• Disturbed riparian areas would be capped with topsoil and seeded from OHW to ten feet outside top bank.
• Lane widening is proposed to be the minimum extent practicable to meet the project purpose.
• Erosion and sediment control devices would be put in place to prevent sedimentation.
• Diversion structure and fill would be temporary and removed after construction of the eight-foot culvert on the unnamed tributary to Caswell Creek; and7.Post construction, the new stream channel would be restored with coir log and brush layering, willow staking, and vegetation mats.
c. Compensatory Mitigation: The applicant has not proposed any compensatory mitigation, stating that the proposed project would replace two damaged and undersized culverts with a box culvert as fish passage improvement, and that the road improvements are required to meet collector road standards. The applicant states that wetland impacts are an extremely small percentage of the overall acreage of the large wetland complexes adjacent to Hidden Hills Road and that impacts collocated with existing disturbance would not negatively impact wetland functions.


After reviewing the application, the Department may certify there is reasonable assurance the activity, and any discharge that might result, will comply with the CWA, the Alaska Water Quality Standards, and other applicable State laws. The Department also may deny or waive certification.

The permit application and associated documents are available for review. For inquires or to request copies of the documents, contact dec-401cert@alaska.gov, or call 907-269-6285. 

Disability Reasonable Accommodation Notice
The State of Alaska, Department of Environmental Conservation complies with Title II of the Americans with Disabilities Act (ADA) of 1990. If you are a person with a disability who may need special accommodation in order to participate in this public process, please contact ADA Coordinator Claire Fishwick at 907-465-5871 or TDD Relay Service 1-800-770-8973/TTY or dial 711 prior to the expiration date of this public notice to ensure that any necessary accommodations can be provided.
 

Attachments, History, Details

Attachments

None

Revision History

Created 4/28/2023 10:38:03 AM by jrschlosser
Modified 4/28/2023 10:38:59 AM by jrschlosser

Details

Department: Environmental Conservation
Category: Public Notices
Sub-Category:
Location(s): Anchorage
Project/Regulation #:
 
Publish Date: 4/28/2023
Archive Date: 5/19/2023
 
Events/Deadlines: