HomeMy WebLinkAboutPD 2020-0036; Plaza Bonita Slope Repair; HYDROLOGY AND HYDRAULICS REPORT FOR PLAZA BONITA SLOPE REPAIR; 2021-05-24HYDROLOGY & HYDRAULICS
REPORT
FOR
PLAZA BONITA SLOPE REPAIR
2210 PLAZA BONITA, LA COSTA, CA
PROJECT# PD2020-0036
DRAWING NO. 527-3A
PREPARED FOR
La Costa Village HOA
Carlsbad, CA 92009
PREPARED BY
Robert 0. Sukup
4322 Sea Bright Place
Carlsbad, CA 92008
RCE 28302
May 24, 2021
HYDROLOGY DISCUSSION
This project was to repair a slope that had a shallow surficial slope failure as a
result of an irrigation pipe leaking. The irrigation pipe was repaired and the slope
was rebuilt. A small flat area at the top of the slope, similar to what existed before
the failure, was determined to need an area drain.
Other than a small 12 S.F. flat roof over the utility cabinet, no other impervious
surface runoff comes into this area. The runoff from the roofs, decks and patios
of the adjacent units is piped into an onsite drainage system. I do not know
where the actual connections and drain lines are, but I was told by more than one
person that is how the building runoff is handled. The flat area we are dealing
with at the top of the repaired slope is extremely small.
The attached exhibits and calculations indicate the proposed 3" diameter PVC
pipe can adequately handle the runoff.
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