HomeMy WebLinkAboutResponse to CommentsRESPONSE TO COMMENTS
ENGINEERING COMMENTS NO. 1 (Construction Documents)
"Final Plat) Missing PUE between Lot 36 and 37 of Block 3.
This pue was added to the plat and the construction drawings
./As you are aware the City required a geo-technical study for The Barracks -Phase 1,
specifically for the areas proposed for public street and right-of-ways based on the long term
existence of ponds on the property. As a result of this study several areas were identified as
weak and were subsequently removed and re-compacted by the developer and the original
proposed street design was allowed to be constructed. Based on the report the public street
and right-of-way areas in Phase 2 were also tested. Please explain the grading and testing
activity to occur during the construction of Phase 2 in order to achieve a properly compacted
soil beneath the proposed street sections.
The fill material placed in Phase 2, either from the pond excavation or fill brought in by trucks, is
being compacted as it is being placed. The fill material under the streets and within the right-of-
way will be tested to see if it meets moisture and density requirements as was done with Phase
1. This testing will be done under the observation of the City's construction inspector. Areas
which do not meet requirements will be reprocessed and compacted until the requirements are
met.
~elated to Comments 1, please document the fill and compaction effort from the cut taken
from the "retention" pond area and placed on the proposed Phase 2 property.
Refer to the response to the previous comment. Fill material placed on the lots will be
evaluated by the geotechnical/foundation engineer who prepares the foundation plans for the
structures and the foundations designed accordingly.
/.{Sheet 3) Inlet 130 is mislabeled in profile.
The label has been revised.
/(sheet 4) Pipe 131 appears to be very shallow and may conflict with the streets sub-grade
and base. Please specify Class Ill or Class IV culvert classification.
The RCP has been specified as Class Ill.
~Sheet 4) Please verify that HOPE is not being proposed in a "structural area" for Pipe 140,
please revise to RCP.
Pipe 140 is not under a street so HOPE pipe is specified with structural backfill.
~heet 5) Pipe 220 appears to be very shallow and may conflict with the streets sub-grade
and base. Please specify Class Ill or Class IV culvert classification.
The RCP has been specified as Class Ill.
~heet 5) Pipe 310, 230, 210: With the proposed storm pipe section being extremely shallow ~~d along rear and side lot lines these pipes needs to be RCP .
The storm sewer pipe design has been revised to use a concrete open channel instead of the
pipe. Pipe 210 is now 24 ' in length with the remainder changed to an open channel. The
channel sections are provided on Sheets 5 and 6. The profile of the channel is the same as the
pipes. Two copiesof the revised Appendix E from the drainage report is attached with the
Storm Sewer Pipe Design Summary updated.
~eet 3 and 5) Please provide a detail of the outlet structure/connection at Pipe 110 and c..1?j~'e 210.
The details of the concrete rip-rap have been added to Sheet 3 at the connection of Pipe 110
and Channel No. 2.
~s it was left in Phase 1 the detention pond was turned into a retention pond with a pool
elevation of 305.5 and was dug much deeper. It appears that the retention pond was never
actually completed with appropriate erosion control, established vegetation, appropriate side
slopes, etc. Is the intent to turn the retention pond back into a dry detention facility? Please
address this effort in the drainage report and construction documents.
Additional grading to the side slopes are proposed to allow construction of Phase 2 and to
flatten the side slopes of the pond. Additional soil improvement, irrigation and other means will
be utilized to establish grass and stabilize the slopes. It is anticipated that the pond will remain
a retention pond.
~the plan is to leave the retention pond as proposed with Phase 1, please update the
Phase 2 plans and report, as to match Phase 1.
The plan is to modify the pond as shown on Sheet 6. The pond HEC-HMS analysis has been
run again with the proposed contours shown on Sheet 6 and the results provided in the attached
addendum to the Drainage Report.
/rhere is a lot of erosion that has taken place in and around the retention facility. These
areas need to be re-established, compacted and re-vegetated prior to acceptance of Phase
2.
Noted, and additional work will be done before Phase 2 is complete.
~ase label the proposed final side slope of the retention facility.
The side slopes for the detention pond are labeled on Sheet 6.
~lease illustrate the proposed construction effort for the retention/detention facility on your
proposed grading plan.
.. ~
The proposed grading is shown on Sheet 6. After the grading is complete, an as-built survey
will be performed and the volume of the pnd computed and the HEC-HMS model run if
necessary.
,Please include the proposed velocities in the sanitary sewer report
The proposed velocities have been added to the report and 2 copies of an Addendum to the
reeo · rovided.
~I se submit street light plan per College Station standards from utility provider.
he street light plans from BTU will be provided at a later time once they have been prepared by
BTU.
~ith this subdivision being BTU electric and with the City of College Station accepting the ~reets, please clarify the intent for street lights? (Please submit solution upon resolution. It
is our understanding that BTU and CSU Electric are discussing these issues at this point,
however at this time the subdivision's HOA is responsible for the monthly electric cost.)
The Developer has an existing contract agreement with BTU to pay for the monthly electric cost
through the HOA.
P addition to the following standard comments, if more than 5 acres will be disturbed during
construction of this project a NOi must be filed with the state and a copy provided to the
CoCS. Storm water management requirements are as follows, any questions may be
directed to Donnie Willis, CoCS Drainage Inspector, at 979-764-6375:
Noted
Additional Information:
2 copies of the revised Engineer's Cost Estimate are attached.
RESPONSE TO COMMENTS
ENGINEERING COMMENTS NO. 2 (Construction Documents)
1. The proposed open channel has been removed and the original design with 2-24" pipes is
now proposed. The pipe material has been changed to RCP .
2. The final side slope has been label as 3.5H :1V, which per our email the City will accept for
the detention pond.
3. The Street Light Plan has still not been completed. We will submit it as soon as we get it
from BTU.
4. A copy of the agreement is attached.
Additional Information:
2 copies of the revised Engineer's Cost Estimate are attached.