A-Mill Hydro Project
Monday, June 30, 2014 at 7:51AMVideo from June 27 Public Meeting
Public Meeting - Friday, June 27
Minneapolis Leased Housing Associates IV, Limited Partnership is pursuing a Federal Energy Regulatory Commission (FERC) license to construct and operate the A-Mill Artist Lofts Hydroelectric Project, located in Minneapolis, Minnesota on the east bank of the Mississippi River at Upper St. Anthony Falls.
To engage with the public and resource agencies, a consultation was held to solicit comments on its proposed license application. This meeting took place at the time and location described below:
Date: Friday, June 27, 2014
Time: 10:00 am
Location: Minneapolis Central Library, Doty Board Room
Download meeting notice & materials...
Detailed Description (from developers website):
The purpose of this project is to restore hydropower to the Pillsbury A‐Mill building. The power will solely be used for the A‐Mill Artist Lofts, which is currently under construction and will provide 251 low‐income apartments. No power will be sold to the grid nor will power in excess of demand be produced. The hydroelectric facility is planned to be installed before the end of 2015 with construction starting as soon as applicable permits are obtained.
The Pillsbury A‐Mill, including the below referenced water infrastructure, was built in 1881. The A‐Mill is one of only 25 National Historic Landmarks in Minnesota. It operated as a flour mill until 2003. Power for the mill was produced by turbines in the building. To power the turbines water was brought in from the Mississippi river via a headrace tunnel. The water flowed down two drop shafts powering two turbines. The water was returned to the river via two tailrace tunnels. The water rights for the power used by A‐Mill have been kept with the property since its establishment. The proposed hydropower project uses approximately two thirds of its water rights or 200 cfs to generate 600 kW of power.
The proposed hydroelectric facility involves two separate sites (Figure 1). The first restores the existing intake structure (Figure 2) sleeves a pipe through the existing tunnel, replaces a turbine and generator in the existing downstream drop shaft, and conveys the turbine discharge through a box culvert placed in the existing outlet channel (Figure 3). Details regarding work outside the building are provided below. The intake structure and outlet structure are on property owned by Xcel Energy and the Minneapolis Park Board, respectively.There is an established legal right for the project owner to maintain these structures.
The intake will involve the reactivation of the former intake into the main headrace tunnel that is located below Main Street. The intake structure is located on the left bank of the Mississippi River, a short distance upstream of Xcel Energy’s now decommissioned Main Street Hydroelectric facility. The intake structure is presently partially closed by a concrete bulkhead. There is two-foot square gated opening that conveys water into the tunnel. Reactivation of the intake will involve removing the bulkhead, installing a trash rack and sluice gate, and dredging localized silty sediment immediately adjacent to the intake structure. The new trash rack is designed to limit approach velocities to 0.5-feet-per-second.
The area immediately out from the intake was probed through the ice in mid-February, 2014. Water depths ranged from 3-feet to over 8-feet below normal water level. The probing clearly identified the presence of relatively deep soft sediments in front of the intake structure. For the intake to be reactivated and function effectively the area immediately in front of the intake will be dredged to the invert of the existing intake structure (~15-feet below the normal water level) tapering up to the existing bed elevation as shown on the attached plans. The estimated volume of dredge material is estimated to be 500 cubic yards.
The new outlet structure will consist of a 4-foot high by 6-foot wide concrete box culvert that will be located on the invert of the historic outlet structure channel. The top of the culvert will be nearly submerged under typical river levels. It will discharge unto the existing submerged apron. Reactivation of the outlet structure will require the removal of silt that has accumulated since the A-Mill ceased operation. There is approximately 100 cubic yards of silt to be removed off the submerged apron and another 160 cubic yards to be removed from the upstream existing tailrace.
Reader Comments (1)
Thank you for taping and posting.
Not sure why a for-profit business should be getting city council grants to explore other for-profits ventures.