HomeMy WebLinkAboutTR 35337 HYDROLOGY REPORT-022 Spyglass Ranch Tract 35337
Hydrology Study
prepared for the multi—family development. These water quality treatment
devices are anticipated to be located within the multi—family development.
Area "C" (JDA Area)
Area "C" is a major drainage area in the post—developed condition that
is comprised of about half of the east side of the site. The comparable
drainage area in the pre—developed, or existing condition is Area 4. This
area is tributary to the adjacent downstream property to the north, namely
Tract 31593, South Shore (see Figure 6).
TRACT 31593
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TRACT 35337
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Figure 6: Developed Areas Tributary to Tract 31593
No Scale
The drainage course of Area 4 exits and enters the Spyglass Ranch
north property line at multiple locations, making it difficult to meaningfully
compare pre—developed and post—developed flow rates. Largely due to the
convoluted nature of Area 4, this drainage area presents a special condition
that is resolved by a drainage acceptance agreement on the part of South
Shore and to the benefit of Spyglass Ranch as part of the overall joint
development agreement (JDA) between the two projects. In other words, it
is mutually agreed upon that there is no requirement for Spyglass Ranch
to mitigate for any incremental increase in runoff due to development that
may enter the South Shore property as a result of Spyglass Ranch
developing its property. The JDA stipulates that South Shore will accept all
of the tributary developed area from Spyglass Ranch. South Shore will
convey and provide the necessary water quality treatment for these storm
flows prior to the waters being discharged to Wasson Canyon Creek.
Since, Area "C" is impacted differently under each of the Stage 1 and
Ultimate scenarios, this study evaluates the drainage area under both
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