HomeMy WebLinkAboutSupporting Engineering InformationBleyl & Associates
Project Engineering & Management
March 2, 2007
Carol Cotter EIT
Planning and Development Services
City of College Station
P.O. Box 9960
College Station, TX 77842
Re: Wolf Creek Condos
Supporting Engineering Information.
Dear Carol,
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Oli Y;.J-{_722 Broadmoor
Suite 210
Bryan, TX 77802
As part ofthis resubmittal of site and construction documents, we have included our
simplified 'response to comments' revisions to the last round of City comments.
However because several of the items warrant more detailed response, I am providing
this letter to address them, but grouped together by discipline rather than comment
number.
Sanitary Sewer Improvements
At this time, an old sanitary sewer line runs partially along the southern edge of the
project then drops several feet at the manhole at the southeast corner of the property.
This line is too shallow to serve the proposed units, therefore a private parallel line was
selected to serve the project, which would tie into the north side of the existing manhole.
However, Spencer Thompson has been very keen on getting the existing line replaced via
city participation, and so far the developer has been receptive, but not willing to slow
down the project to await council's action on an OP request, or commit to building a
public line without a commitment of reimbursement.
Bryan
(979)-268-1125
(979)-260-3849
Austin
(512)-328-7878
(512)-328-7884 Fax
Conroe
(936)-441-7833
(936)-760-3833 Fax
Because we know Spencer is working on the OP, we just happen to have a working
design for a public sewer line that will replace the current one, as well as extend it
westward to pick up all the buildings. Once the OP is approved, or the developer is
convinced that the OP is committed, we will remove the private sewer line from the plans
and add a public sewer line improvement sheet to the plan set.
In the mean time, we have shifted the private line out of the existing easement, and added
cleanouts and slopes as requested by the comments.
Public Water Improvements
While this project only requires a public line to reach the fire hydrant in the middle of the
project, the developer agreed to extend the line to the end of the property (rather than a
shorter loop into the Arbors Apartments) to assist the Steward Project which absolutely
needs the connection to obtain fire flow.
For this reason, we believe that the water lines in both projects will be constructed almost
simultaneously. Even if something happened to delay the Stewart Project, it's necessity
of connecting to obtain fue flow means that the City will not be left with a permanent
dead end line.
Therefore while we understand the need for these plans to include the blow off at the
west end, and therefore have included it, the fue flow velocities, line lengths etc are all
based on this line being connected to another public line at the west end as required.
We noted the request to shift the line north to shift some fittings out from under the
paving, however doing so would eliminate several trees intentionally preserved by the
developer. Because this design district has such a significant emphasis on tree
preservation, we have left the water line under the area already disturbed.
We note that there is an existing line valve on the I2 inch George Bush line just south of
the bridge, which precludes the need for the second tee valve at this connection point.
In response to the fire flow report, we offer the following information. The largest
building is 5080 sf in area. Assuming the worst possible construction designation (type
VB, IFC table BIOS.I requires 2000 gpm. IFC table CI05.I translates this flow into a
requirement for 2 hydrants, which are provided for the project.
Storm Drainage
At present the site, along with a narrow portion of the Arbors Apartments, drains
northward into Wolf Pen Creek. Two channels form on the site such that about 2/3 of the
runoff is contained within these areas, while the rest continues towards the creek in a
sheet flow condition.
The proposed drainage pattern will mimic the existing by conducting the runoff into the
two established drainages, as well as letting two smaller areas of landscaping (not
surfaced) continue to sheet flow as before.
Even at 100 year flow levels, the developed project, along with the flow contributed by
the Arbors, will only total 36 cfs, which as mentioned above, will be spread between the
two sheet flow areas and the two channel discharge points.
Floodplain I Floodway
While the review comment requested showing the floodplain per the 1999 LOMR , the
developer was provided copies of the 2000 LOMR by Alan Gibbs at the beginning of the
project, and being the most recent is what we have shown on the plans.
While fill is proposed within the flood fringe, no fill will be allowed within the small
portion of floodway located near buildings 1 and 2 due to the overhanging nature of the
deck construction.
As always, we stand ready to meet and discuss any issues regarding this project at your
convenience.
Encl: Letter Acknowledging City Standards
International Fire Code Tables B105.1 and C105.l