PA1301-CS150226 ... cot_ _ (3,0
■■ HALFF
February 26, 2015
AVO 28540 X002 TA02
Board of Directors
Denton County Levee Improvement District No. 1
C/O Julianne Kugle
1980 Post Oak Blvd., Suite 1380
Houston, Texas 77056
Re: Review of plans and Conditional Letter of Map Revision (CLOMR) submittal by
Teague Nall & Perkins — Andrew Brown Park & Denton Creek Pedestrian
Bridge
Dear Board of Directors,
We have completed a review of the plans and Conditional Letter of Map Revision
(CLOMR) for the Andrew Brown Park & Denton Creek Pedestrian Bridge prepared by
Teague Nall & Perkins. This general review consists of checking the submittal package
for potential impacts to the levee and channel improvement section of Denton Creek
operated and maintained by the Denton County Levee Improvement District No. 1
(DCLID-1).
The following comments are a result of this review:
1. All comments pertaining to the CLOMR submittal have been addressed to our
satisfaction and no further action is required.
2. All comments made on the plans pertaining to the proposed trail crossing of Denton
Creek have been addressed to our satisfaction and no further action is required.
3. The easement document for the proposed trail crossing of Denton Creek must be
executed and recorded prior to commencement of any work on DCLID-1's
property.
Based on this information, Halff Associates recommends conditional approval. Full
approval can be granted once Item 3 above has been addressed.
This review was performed for the benefit of the Denton County Levee Improvement
District No. 1. This is not a detailed engineering review of any construction plans, and
Halff Associates, Inc. assumes no liability for the adequacy of the planning, design or
construction of the project.
HALFF ASSOCIATES,INC.
1201 NORTH BOWSER ROAD TEL (214)346-6200 WWW.HALFF.COM
RICHARDSON,TX 75081-2275 FAX (214)739-0095
Elm HALFF
Do not hesitate to call me at 214-346-6245 if you have further questions or comments
concerning this review. Please include the reference "AVO 28540"on all correspondence.
Sincerely,
HALFF ASSOCIATES, INC.
44s.tec /E
Russell P. Erskine, P.E., CFM
Project Manager
C: Niraj Acharya, P.E., CFM
Teague Nall & Perkins
Mike Garza, P.E.
City of Coppell
John Elias
City of Coppell
UI HALFF
January 14, 2015
AVO 28540 X002 TA02
Board of Directors
Denton County Levee Improvement District No. 1
CIO Julianne Kugle
1980 Post Oak Blvd., Suite 1380
Houston, Texas 77056
Re: Review of Floodplain Study Submittal by Teague Nall & Perkins — Conditional
Letter of Map Revision (CLOMR) for Denton Creek Pedestrian Bridge
Dear Board of Directors,
We have completed the technical review of the Conditional Letter of Map Revision
(CLOMR)for Denton Creek Pedestrian Bridge prepared by Teague Nall & Perkins, dated
April 30, 2014, revised on August 13, 2014, revised on October 31, 2014, revised on
December 16, 2014, and received on December 18, 2014. This general review consists of
checking the submittal package for potential impacts to the levee and channel improvement
section of Denton Creek operated and maintained by the Denton County Levee
Improvement District No. 1 (DCLID-1), and checking the submittal package for
completeness and compliance with the City of Coppell floodplain ordinances, regulations,
and policies.
The following comments are a result of this review:
1. The proposed project seems to have no significant impact on water surface
elevations on Denton Creek.
2. The proposed project seems to have no significant impact on velocities on Denton
Creek.
3. Valley storage loss on Denton Creek due to the proposed project does not exceed
the maximum allowable of 15%.
4. A final report that has been sign and sealed by a Professional Engineer in the State
of Texas will need to be submitted before final approval is granted.
Based on this information, Halff Associates recommends conditional approval. Full
approval can be granted once Item 4 above has been addressed.
HALFF ASSOCIATES,INC.
1201 NORTH BOWSER ROAD TEL (214)346-6200 WWW,HALFF.COM
RICHARDSON,TX 75081-2275 FAX (214)739-0095
:C: HALFF
This review was performed for the benefit of the Denton County Levee Improvement
District No. 1 and the City of Coppell. This is not a detailed engineering review of any
construction plans, and Halff Associates, Inc. assumes no liability for the adequacy of the
planning, design or construction of the project.
Do not hesitate to call me at 214-346-6245 if you have further questions or comments
concerning this review. Please include the reference"AVO 28540" on all correspondence.
Sincerely,
HALFF ASSOCIATES, INC.
i� tk 4
Russell P. Erskine, P.E., CFM
Project Manager
C: Niraj Acharya, P.E., CFM
Teague Nall & Perkins
Mike Garza, P.E.
City of Coppell
John Elias
City of Coppell
UMW HALFF
December 23, 2014
AVO 28540 X002 TA02
Board of Directors
Denton County Levee Improvement District No. 1
C/O Julianne Kugle
1980 Post Oak Blvd., Suite 1380
Houston, Texas 77056
Re: Review of Final Review Plans - Not for Construction Submittal by Teague Nall &
Perkins—Andrew Brown Park& Denton Creek Pedestrian Bridge
Dear Board of Directors,
We have completed a review of the Final Review Plans —Not For Construction for the Andrew
Brown Park & Denton Creek Pedestrian Bridge prepared by Teague Nall & Perkins, dated
October 13, 2014, and received on December 11, 2014. This general review consists of checking
the submittal package for potential impacts to the levee and channel improvement section of
Denton Creek operated and maintained by the Denton County Levee Improvement District No. 1
(DCLID-1).
The following comments are a result of this review:
DCLID-1
1. Please include the following notes in the "General Notes" section of the plans:
a. "The safety of the Denton County Levee Improvement District No. 1 (DCLID-1) is of
paramount importance during this contract. The contractor shall be responsible for
the safety and unhindered operation of the flood protection facilities at all times
during construction. In the event of an actual or anticipated flood on Denton Creek,
or when ordered by the DCLID's Operations and Management Manager or DCLID's
Engineer, the contractor shall take immediate action to restore the levee system to full
operating condition. Such action shall include, but not be limited to: 1) temporarily
backfilling any excavation of the levee embankment: 2) Clearing all construction
equipment from all DCLID-1 access and patrol roads. The contractor shall be
available to take such remedial action 24 hours per day, 7 days per week during the
contract time. Failure of DCLID's O&M Manager or Engineer to inform the
contractor of a flooding event anticipated or in progress, shall in no way reduce the
contractor's responsibilities."
b. "Construction will take place on DCLID-1 right-of-way. Before any work begins in
these areas, the contractor shall contact DCLID-1. Extreme care shall be taken to
HALFF ASSOCIATES,INC.
1201 NORTH BOWSER ROAD TEL (214)346-6200 WWW HALFF COM
RICHARDSON,TX 75081-2275 FAX (214)739-0095
H! HALFF
protect the levees and drainage facilities. In the event that the contractor's operations
cause rutting or erosion of the ground within the DCLID-1 or private rights-of-way,
the contractor shall restore the area to a condition equal to or better than its condition
prior to construction. Contractor shall secure approval for any haul roads within or
crossing these or other private rights-of-way."
c. "At the end of construction, the contractor shall restore all surfaces used for haul
roads to their condition prior to construction. All dirt used to construct haul roads
shall be removed. Such restoration shall be at the contractor's expense and shall
include regrading, grassing, repairs to landscaping, repairs to existing facilities, and
any other work required to bring these areas back to their condition prior to
construction."
d. "The contractor shall not place fill in the floodways of Denton Creek, except as
directed in the plans. The contractor shall not temporarily stockpile material within
the floodway without prior written permission from DCLID-1."
2. Please include the following notes under a section titled "Flood Emergency Action Plan":
a. "Approval of a Flood Emergency Action Plan must be obtained in writing prior to
start of construction on the levee. The plan shall address, in detail, steps to be taken
by the contractor to include,but not limited to the following:
i. Quantities and locations of stockpiles of suitable impervious material for
backfilling open excavations. Impervious material considered suitable for this
purpose is that material classified in accordance with ASTM D 2487 as SC, CL,
or CH. Stockpile quantities to be maintained shall exceed the volume of open
excavations within the floodway by factor of two (2). Stockpiles shall be
maintained near the open excavation area.
ii. Measures for protecting excavations for flood discharges up to and including the
100-year flood.
iii. Procedures and equipment to be utilized for backfilling operations.
iv. Time frames for implementing emergency actions.
v. Name and phone number of contractor's point of contact (and at least one
alternative) for emergency actions."
b. "The decision to commence emergency actions will be made by DCLID-1. In
making its decision, DCLID-1 will take into consideration data from the National
Weather Service and River Forecast Center; as well as localized flood-fighting
activities that may be ongoing. Upon notification from DCLID-1, the contractor's
emergency action point of contact (or alternative) shall be responsible for insuring
that emergency actions are implemented as directed by DCLID-1."
c. "Denton County Levee Improvement District No. 1 contact information is as follows:
Contact:
Mr. Richard (Dick) Hightower, District O&M Manager
Cell: (214) 769-3297
Office: (214) 352-5118
NE HALFF
Mr. Russell P. Erskine, District Engineer
Cell: (214)477-6223
Office: (214) 346-6245
3. Please include the following notes under a section titled"Inspection of Levee Work":
a. "The levee shall be kept free of equipment and materials during times when no
construction activity is taking place on the levee."
b. "DCLID-1 and its representatives shall have the right to inspect all work which
pertains to District facilities (channel and levee) at all reasonable times and shall have
full and complete access to all inspection and testing report."
4. Please add Denton County Levee Improvement District No. 1 to Note 11 under "Metal
Truss Notes"on Sheet 33 of 39.
5. Please verify the 100-year (Effective) water surface elevation shown on Sheet 34 of 39.
The water surface elevation from the hydraulics model differs from what is shown on the
sheet.
6. The granular fill shown on Sheet 38 of 39 should not extend laterally beyond the riprap
without a clay cap.
7. Proper drainage from behind the concrete riprap should be provided near the toe of the
slope. Currently, the plans show only weepholes in the granular material near the
abutment as shown on Sheet 38 of 39.
8. Vertical movement of the riprap caused from the shrink/swell characteristics of the
supporting soil should be expected and designed for.
9. Will temporary construction easements from DCLID-1 be required? If so, will it be the
Contractor's responsibility to obtain these from the District?
10. The Erosion Control Plan; once developed should be submitted to the District for review
and approval prior to construction.
11. Once the plans have been approved by DCLID-1 and an exhibit has been provided, the
District's Lawyer will prepare the required easement for the proposed trail crossing of
Denton Creek. Be advised that the easement document must be executed and recorded
prior to commencement of any work on DCLID-1's property.
This review was performed for the benefit of the Denton County Levee Improvement District
No. 1. This is not a detailed engineering review of any construction plans, and Halff Associates,
Inc. assumes no liability for the adequacy of the planning, design or construction of the project.
®; HALFF
Do not hesitate to call me at 214-346-6245 if you have further questions or comments
concerning this review. Please include the reference "AVO 28540" on all correspondence.
Sincerely,
HALFF ASSOCIATES,INC.
EtAki'qj
Russell P. Erskine, P.E., CFM
Project Manager
C: Niraj Acharya, P.E., CFM
Teague Nall & Perkins
Mike Garza, P.E.
City of Coppell
John Elias
City of Coppell