ST8804-CS 881117 4P Jerry Parch Consulting Engineers
November 17, 1988
Mr. Jay Chester, P.E.
ABQ Development Corporation
P O Box 25625
Albuquerque, NM 87125
505/242-3330
RE: JP No. 88009; Parks of Coppell;
Heartz Road; Sanitary Sewer Study; Coppell, Texas
Dear Jay:
Pursuant to the City of Coppell's review comments for the Heartz
Road preliminary plat, we have prepared a study of the sanitary
sewer in Heartz Road from Sandy Lake Road to Parkway Boulevard.
The purpose of our study was to evaluate sanitary sewer flows in
Heartz Road with fully developed conditions of development in the
service area based on existing land uses in developed areas and
current zoning in undeveloped areas. These discharges were then
compared to capacities in the existing eiGht-inch sewer line. If
existing capacities are deficient, we determined sewer pipe sizes
necessary to obtain the required capacity to adequately serve the
area upon full development.
Enclosed is a
~~~i~between .... manholes in the existing sanitary
Road. Also sho ??l sewer
pipe needed to provide total capacity
flow, where required. It is assumed that" a par p pe ~ill be
constructed on the same slope as the existing pipe.. Manhole
locations are shown on the service area exhibit also enclosed.
The design flow at each sanitary sewer manhole (SSMH) on the
existing sewer line north of Sandy Lake Road was established
~? ba~ed upon "Ultimate Development" conditions using Harmon's
,~ Formula for Peak Flow with an additional infiltration factor of
~-~<~750 Gpd/ac. This design method is used by the City of Fort
Worth. The infiltration factor is adopted from methods used by
the City of P1 no ~ ~ ~ ~ /
The results of o~r study indicate that the two upstream sections
of the existin~ s~wer lin~in proposed Heartz Road between SSMH#6
and SSMH#4 a~ to serve the upstream service area.
However, the re--the existing system, approximately 1930
L.F., from SSMH#4 to Parkway Boulevard, is inadequate and will
require the construction of a parallel line. The size and
lengths of additional pipe required for ultimate development of
the service area are listed in the table. A single pipe
equivalent has also been calculated for each section in case you
6001 V,/. Interstate 20, Suite 209, LB 32 · Arlington, Texas 76016 · Metro 1817J 572-3458 · 1817) 561-2108
Mr. Jay Chester, P.E. November 17, 1988
JP No. 88009 Page 2 of 2
elect to remove the inadequate sections and install a single
sanitary sewer line ha~ing the required flow capacity.
We have also investigated whether the existing sanitary sewer in
Heartz Road is sufficiently deep to permit service laterals to
serve your property on the east side of the channel that
parallels Heartz Road without requiring aerial crossings. Using
surveyed channel bottom elevations and sewer pipe flow line
elevations obtained at existing manholes, it appears that__~
existing se~~~ ~~'L3~'~ '
'~~ Therefore, lateral pipes crossing the ch~ - De
?~~e existing channel bottom.
We will proceed with an evaluation of the sanitary sewer
extending north across the 27.5 acre tract north of Parkway
Boulevard. This sewer receives flow from the Heartz Road
sanitary sewer and sewers in Parkway Boulevard.
We will submit this evaluation of the Heartz Road Sanitary Sewer
to the City of Coppell following your authorization. If you have
any questions or require any additional information, please do
not hesitate to call.
Sincerely,/q
Jerry Parche', P.E.
JP:ch
Enclosure: Table of Discharges and Pipe Capacity
Service Area Exhibit