Hidden Valley-CS040405OWDEY, ANDERSON
& ASSOCIATES, INC.
CIVIL ENGINEERS
5225Village Creek Drive
Suite 200
Piano, Texas 75093
972-91.0694
972.911-9538 Fax
April 5, 2004
Mr. Keith Marvin
City of Coppell
255 Parkway
Coppell, Texas 7501 9
RE: Engineering review comments to Hidden Valley civil construction plans.
Mr. Marvin:
This letter is to address the comments in your letter dated March 5, 2004.
General
1. The Tree Mitigation plan has been removed from the plan set.
Paving Plan & Profile - Sheet 1
1. Full width reconstruction of Hidden Valley Dr. will not be required to install the two proposed
curb inlets. Reconstruction will be limited to the concrete curb and gutter.
2. Adequate spacing between new curb inlets and new driveways is provided for gutter transition.
3. The fill required between Sta O+OO to Sta 2+00 does not create drainage problems for the
adjacent lots. Positive drainage will still exist from the adjacent lots to Hidden Valley Dr.
Paving Plan & Profile - Sheet 2
t. The Hidden Valley Dr. profile has been realigned to match the plan view.
2. Dimensions have been shown on the cul-de-sac.
Drainage Area Map
1. The profile for Hood Court shows a top of curb profile for both the right and left side of Hood
Court ending at the midpoint of the curve that defines the cul-de-sac.
Drainage Area Map
1. Based on my field inspection, area A1 drains to the inlet in the church parking lot.
2. The proposed inlets have been relocated to better collect the stormwater in Hidden Valley Dr.
Storm Sewer Plan & Profile
1. Addressed above
2. A note has been provided to construct the top of the inlet located at the northeast corner of the
church parking lot.
3. The area of proposed rock riprap has been increased from 12'x10' to 20'x15'. The combination
of the velocity dissipaters and rock riprap should substantially reduce the velocity and potential
for erosion.
Water and Sanitary Sewer Plan
1. The proposed 8" water line has been connected to the existing 6" water line.
2. The cleanout at Sta 5+30 has been noted as a 6" cleanout
3. A note has been added instructing the contractor to televise the existing 6" for city inspection
prior to connecting services for lots 1-3.
4. The existing 8" sanitary sewer has been shown down to Meadowcreek Rd.
5. A 500 maximum spacing has been maintained for the inline water valves.
6. Water and sanitary sewer services have been relocated so that the water services is located at
the center of the lot and the sanitary sewer service is located 10' downstream of the water
service.
Sanitary Sewer Profile
1. A utility bridge has been provided for the 24" RCP where it crosses the proposed 8" sanitary
sewer.
2. The cleanout at the end of Line A has been noted to be 6".
Grading Plan
t. The natural grade of lots 1-3 of block A is roughly 7' - 9' higher than that of the natural grades in
the street that fronts those lots. A maximum driveway grade of 10% prevents us from raising the
pad any higher. While we did rework the vertical alignment of Hidden Valley in an effort to raise
the street in this area, the existing driveway immediately west of lot 1, block A limits how high we
can raise the street.
2. Retaining wall details have been added to this plan set.
3. The retaining wall will extend 6" above natural grade where existing driveways back up to the
north property line of lots 1-3, block A
Erosion Control Plan
1. A copy of the executed NOI will be provided at the pre construction meeting.
2. We will work with the contractor in developing a plan to maintain access to the homes affected
by construction.
Scott D. Caruthers, P.E.