HomeMy WebLinkAboutFile Documents.196 Pfister Dr.0107-2023-BRES (8) JOSS ARCHITECTURE+ PLANNING
605 EAST MAIN STREET ASPEN, COLORADO 81611
(t) 970/925-4755 (f) 970/920-2950 MEMORANDUM
TO: Kyla Smits, Engineering Proj. Mgr. VIA E-MAIL 22238.00
2 Pages Including Cover
CC: Chris Doody(GFS), Celia Liu (CGA), Bob Campbell and Dean Arneson (SHC), Les Rosenstein and
Jonathan Nassar(Poss),Sydney Fallon (Building)
FROM: Richard L. de Campo
Bill Poss and Associates Architecture and Planning, P.C.
DATE: September 13, 2023
RE: Drainage Narrative for Reduction of Existing Water Feature at 196 Pfister Drive ® ENCLOSURE
Permit#0107-2023-BRES
As requested yesterday, we are submitting a drainage narrative relative to Permit #0107-2023-BRES at
196 Pfister Drive.
Although there is extensive hardscaping and landscaping already existing at the subject property, this
project entails:
1) No alteration to existing hardscape and softscape;
2) No change in soil grade;
3) Slight change of drainage pattern from the existing 157 sf water feature (whose overflow is piped to an
existing drywell system) into 17 sf(remaining part of water feature + 1/2 fountain enclosure) continuing
to use the existing overflow, and 140 sf into a new planter, fully below the level of the existing patio,
and which will drain into the soil below;
4) 12 sf addition to impervious horizontal surface material, consisting of a decorative fountain enclosure
(impervious,tiled top surface), half of which drains into the 11 sf remainder of the existing water feature,
and half drains into the new planter (recessed below patio level) that had been the majority of the
existing water feature;
5) No addition in hard surface patio area;
6) No increase in the footprint of a structure; and
7) No addition of snowmelt.
There is ZERO change in the existing hardscape runoff to existing patio drains or existing softscape runoff
to subsurface drains behind retaining walls. The sole net drainage change is that 10% of the existing water
feature area will still utilize the existing overflow drain (but with 90% less flow), and 90% of the existing
water feature will be converted into a (pervious) planter (with similar landscaping to existing), resulting in
more rainfall absorbed on-site. This is beneficial improvement from a stormwater management perspective.
The existing spa is simply being cleaned, broken tiles replaced, re-grouted, with the edge of the existing
coping being radiused for comfort. That part of workâtiling and finish work - even appears to be exempt
from permit per Exception #7, 2021 IBC A105.2. There is no change in drainage or runoff due to the spa
cosmetic repairs.
1. The area of scope of work is depicted on Sheet A-101. The existing spa was noted as 79sf in area;
although the existing water feature area was not called out, it is 157 sf.
2. As for describing the site, hopefully the old adage "a picture is worth 1000 words" applies with the
photo on A-501 showing the existing conditions and context.
JOSS ARCHITECTURE+ PLANNING
3. The project was described in the permit application as: "re-tiling existing spa; demolition of raised
water feature and most of basin; smaller fountain at end of basin." There is no change to land-use
or soil type. The minor changes in drainage have already been addressed.
4. No existing drainage issues. (In terms of problems or concerns.)
5. No changes to drainage basin, changes in direction, or new outfall. Previous overflow drainage at
the existing water feature is 90% reduced, going into a recessed (-6" below patio hardscape)
planter instead.
6. As already discussed, this project reduces runoff (overflow from water feature) into the existing
drywell system, and increases on-site infiltration.
7. The existing stormwater system (drains piped to on-site drywells)is unchanged by this project, and
no adjoining properties nor right-of-way are impacted.
8. The drainage load on the existing on-site stormwater system will be slightly reduced as a result of
this project.
9. 6 sf of the new fountain enclosure (half of top surface)will drain into the remaining decorative pool,
but keep in mind that it's offset by 140 sf of the existing water feature area being changed to infiltrate
directly into the soil of the new planter.
We hope you will be able to sign off on approving this permit very soon. Should you or anyone else from
Community Development want to review this project on-site, I would be happy to explain the scope of work
in context and address any concerns you may have. 15 minutes on-site would probably be more useful
than further responses to standard checklists. Thank you for expeditious review of this matter.
Respectfully submitted,
Richard L. de Campo, AIA Emeritus, PE Ret., CSI Ret., LEED-AP
Adjunct Principal