Memo on water main additions and retaining wall project, May

NYC 9/11 Public Portal Document

03/10/2024 00:40 212-669-4980 PAGE 08/25

V . GRIGG & DAVIS ENG iEERS,PVC. 2l Crossway .Scarsdale, NY 10583 Telirax (914)725-5095

March 12,2010

Community Board 8 Land Use Committee Charles Moerdller, Chairman 5676 Riverdale Avenue. Suite 100 Bronx. NY 10471-2194

Re: Pre-Construction Surveys for existing Buildings and Retaining Wall, Periodic Monitoring of Retaining Wall Stability during construction. and Post-Construction Surveys for existing Buildings along Cannon Place — Bronx. NY

Dear Mr. Moerdler:

The Fort Independence Park Neighborhood Association has retained Grigg & Davis Engineers, P.C. to provide them with Professional Engineer's recommendations for the prolection of their private property and the dry-laid rubble stone retaining wall along the west side of Cannon Place during the proposed construction of a new Building between Cannon Place and Fort Indcpendencc Street.

On March 5.2010 1 visited the Site and observed the following:

1. The retaining wall is on the west side of Cannon Place and is constructed of rubble stone without mortar ( dry-laid). The height of the retaining wall varies and has a maximum height of approximately 20'-0". The top of the retaining wall is approximately 7'-0" away from the west curb of Cannon Place. See Photograph 1. The facc of the retaining wall has several areas where the rubble stone has %hided outward and is bowing. An appmxirnatcly 20'-0" long section of the retaining wall has been replaced with a poured concrete retaining wall. See Photographs 2 and 3. The eonStruction,joints at each end of the poured concrete section of retaining wall indicate that the retaining wall has continued to move since the poured concrete section was installed, Photograph 4 is the southern construction joint and Photograph 5 is the northern construction joint.

2. The concrete sidewalk at the south end of the retaining wall is in very poor condition due to settlement. See Photograph 6. This settlement is being caused by the loss of the fine soil particles through the retaining wall due to ground water movement. In Photograph 2 the light brown color on the face of the retaining wall is the fine soil particles being washed out.

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