CC - Retention Pond and Seepage Bed DetailsV
13.51'of12"PVC ®
�i ilj
10.26' of 12" PVC ® 0.50%�
INLET A
3 N.:712760.4885
E.:2462522.0821
RIM:2615.89 a
SUMP:2611.93
INV OUT:2612.93 12" (E)
3 SGT A
G2RIM: 2615.66'\
INV IN: 2612.88' 12" PVC (W)J
INV OUT: 2612.53' 12" PVC (N)
3 INLET BAFFLE: 2612.28'
OUTLET BAFFLE: 2612.78':
3 I
4" MINIMUM TOP SOIL
TOP OF POND
ELEVATION = 2615.00'
REVEGETATE POND WITH DROUGHT
TOLERANT GRASSES (NO TURF),
3:1 AS APPROVED BY THE CITY 3:1
III -III- 100-YEAR FLOOD IIII-III
III -III- ELEVATION = 2614.75' I III
-III-III I I:III ::-
-III BOTTOM OF POND III -III
ELEVATION = 2612.00' SAND FILTER PER IDEQ BMP 12
III=III TO FREE DRAINING MATERIAL IIIIII-III-
:III I IIIIIIIIIII'
-III=1 1.0% - '.°% III III III I
I -1 I IIIIIII-III- I IIIIIIIIIIIII1 I I' �'- '
-III-I i IIII-III .,' I III I I_ I I �- I I I
SEASONAL HIGH GROUNDWATER_ _
ELEVATION = 2607.50't
3' MIN SEPARATION TO GROUNDWATER
NOTES:
1. CONTRACTOR SHALL NOTIFY THE ENGINEER IMMEDIATELY IF GROUNDWATER IS ENCOUNTERED ABOVE THE ANTICIPATED SEASONAL HIGH GROUNDWATER ELEVATION.
2. CONTRACTOR SHALL INCORPORATE ALL POND REQUIREMENTS PER IDEQ BMP 23.
3. ALL BASINS TO BE VEGETATED, INCLUDING SLOPES AND BOTTOM. SLOPES SHALL HAVE IRRIGATED TURF GRASS AS SPECIFIED PER THE LANDSCAPE PLANS. NO
IRRIGATION ON BASIN FLOOR. NO WOODY VEGETATION BELOW 100-YEAR WATER SURFACE OR WITHIN 10' OF EMBANKMENT SPILLWAY, PIPES OR STRUCTURES.
SEE ACHD STORMWATER MANAGEMENT BASIN REVEGEEATION GUIDANCE MANUAL AND SPECIFIC BMP'S FOR ADDITIONAL VEGETATION REQUIREMENTS.
4. EXCAVATE AND SCARIFY SUBSOIL BEFORE TOPSOIL/AMENDED SOIL IS PLACED. VEGETATE AFTER CONTRIBUTING DRAINAGE AREA HAS SITE SEDIMENT & EROSION
CONTROL MEASUREMENTS IN PLACE.
5. AREAS DESIGNATED FOR BASINS SHALL BE CLEARED, GRUBBED AND STRIPPED OF TOPSOIL. TOPSOIL SHALL BE STOCKPILED AND USED AT FINAL GRADING TO
ESTABLISH VEGETATION.
6. FILL MATERIALS FOR EMBANKMENT SHALL CONFORM TO UNIFIED SOIL CLASSIFICATION, SC, CH, OR CL AND MUST HAVE AT LEAST 30% PASSING THE #200 SIEVE.
AREAS ON WHICH FILL IS TO BE PLACED SHALL BE SCARIFIED PRIOR TO PLACEMENT OF FILL. EMBANKMENT FILL SHALL MEET ISPWC CLASS C COMPACTION
REQUIREMENTS. CONSIDERATION MAY BE GIVE TO THE USE OF OTHER MATERIALS IN THE EMBANKMENT IF DESIGNED BY A GEOTECHNICAL ENGINEER.
7. ALL PIPE OUTLETS TO BASINS SHALL BE UNEXPOSED AND FULLY BURIED WITH METAL END SECTION TO PREVENT DEGRADATION OF THE PIPE FROM WEATHER.
RETENTION POND A
SCALE: NTS
18.91'of 12" PVC 01
72.78' of 18" PVC @ 0.00%
as as as as
I� I
_,
INLET B2
N.:712751.5666
E.-2462757.1418
RIM:2618.34
SUMP.2614.34
INV OUT:2615.34 12" (S)
2
SGT B2
IRIM: 2618.22'
INV IN: 2612.94' 12" PVC (N)
IINV OUT: 2612.19' 12" PVC (S)
INLET BAFFLE: 2612.34'
OUTLET BAFFLE: 2612.34'
I� I
D I�
II
i�
SEEPAGE BED DIMENSIONS AND CALCULATIONS TABLE
SEEPAGE BED
BED LENGTH
BED WIDTH
BED DEPTH
FINISHED GRADE
TOP OF DRAIN
PERFORATED PIPE
BOTTOM OF DRAIN
GROUND WATER
100-YR VOLUME PROVIDED
ELEVATION
ROCK ELEVATION
INVERT ELEVATION
ROCK ELEVATION
ELEVATION
SB-B
161.0'
10.0'
4.6'
2616.88't
2614.60'
2612.19'
2610.00'
2607.00't
4,057 CY (INCLUDES 25% FOR SEDIMENT)
NOTES:
1. REFER TO THE GEOTECHNICAL REPORT PREPARED BY ALLWEST, LLC DATED SEPTEMBER 24, 2021. SEASONAL HIGH GROUNDWATER WAS NOT OBSERVED IN TEST PITS REACHING A DEPTH OF 13' BELOW EXISTING
GROUND AROUND THE SEEPAGE BED AREA.
2. CONTRACTOR SHALL NOTIFY THE ENGINEER IMMEDIATELY IF GROUNDWATER IS ENCOUNTERED ABOVE THE ANTICIPATED SEASONAL HIGH GROUNDWATER ELEVATION.
3. INFILTRATION RATE USED FOR DESIGN WAS 8.0 IN/HR. SEE GEOTECHNICAL REPORT MENTIONED IN NOTE 1 FOR ADDITIONAL INFORMATION.
® KEYNOTES
1. INSTALL GROUND WATER OBSERVATION WELL PER DETAIL SHEET C5.1.
MONITORING WELL SHALL CONFORM TO THE SPECIFICATIONS AND
REQUIREMENTS PER ACHD STORMWATER DESIGN GUIDELINES 8200
DETAIL 6. THE PORTION OF THE PIPE LYING IN DRAINAGE SAND MUST
BE WRAPPED IN A DRAINAGE GEOTEXTILE, TYPE I PER ISPWC SECTION
2060.
2. INSTALL ONE (1) 1000 GALLON SAND AND GREASE TRAP PER ISPWC
STANDARD DRAWING SD-624. BAFFLE SPACING SHALL BE 20".
3. INSTALL 161.0'x10.O'x4.6' SEEPAGE BED (SB-B). EXTEND DRAINAGE
FACILITIES V (MIN.) INTO FREE DRAINING MATERIAL. CONTRACTOR TO
VERIFY SEEPAGE BED IS A MINIMUM OF 25' FROM ANY DOMESTIC
WATER LINE.
4. INSTALL PERCOLATION POND (POND A) PER DETAIL THIS SHEET.
TOTAL RUNOFF VOLUME + 10% SEDIMENT = 2,775 CF
TOTAL POND VOLUME
TOTAL VOLUME = 2,881 CF (PROVIDED)
TOTAL VOLUME = 2,523 CF (REQUIRED)
PEAK 100-YEAR WATER ELEVATION = 2614.75'
GROUNDWATER ELEVATION = 2607.50'f
POND BOTTOM AREA = 458 SF
POND TOP AREA = 1,545 SF
POND BOTTOM ELEVATION - 2612.00'
POND TOP ELEVATION = 2615.00'
5. OUTFALL
PROVIDE METAL END SECTION AND TRASH RACKS FOR OUTFALL.
INSTALL ENERGY DISSIPATION DEVICE, ROCK RIP RAP OPTION, PER
ISPWC SECTION 206 AND 2050.
SHEET NOTES
A. SEE SHEET C1.1 FOR GENERAL AND UTILITY NOTES.
B. SEE SHEET C5.1 FOR DETAILS AND ADDITIONAL INFORMATION.
C. PROVIDE WATER -TIGHT SEALS AT PIPING ENTRANCES/EXITS FOR SAND
AND GREASE TRAPS AND CATCH BASINS.
D. ALL STORM PIPE WITHIN ROW SHALL BE C900, WHERE COVER OVER
PIPE IS LESS THAN 2 FEET. OUTSIDE OF ROW, STORM PIPE SHALL
BE ADS N-12 HP PIPE OR APPROVED EQUAL. PLOWABLE FILL SHALL
BE USED WHEN LESS THAN 5-FEET OF SEPARATION BETWEEN
STRUCTURES. IF VERTICAL SEPARATION DISTANCE FROM WATER IS
LESS THAN 18 INCHES, STORM PIPE SHALL BE C900 OR APPROVED
EQUAL.
E. ALL DRAINAGE STRUCTURES SHALL BE PER ISPWC STANDARDS AND
THE ACHD SUPPLEMENTS TO THE ISPWC. STORM DRAIN STRUCTURES
SHALL HAVE HS-25 TRAFFIC RATED LIDS UNLESS OTHERWISE
SPECIFIED.
F. THE CONTRACTOR SHALL COMPLY WITH ALL THE REQUIREMENTS FOR
STORM WATER DISCHARGE ASSOCIATED WITH CONSTRUCTION ACTIVITY.
THIS INCLUDES IMPLEMENTING THE BMP'S RECOMMENDED IN THE
SWPP PLAN PREPARED FOR THIS SITE, REGULAR SITE INSPECTIONS
DOCUMENTATION OF MODIFICATIONS TO THE SWPPP AND OTHER
REQUIREMENTS AS SET FORTH IN THE NPDES GENERAL PERMIT.
G. ALL CHANGES REQUIRE APPROVAL BY THE DESIGN ENGINEER AND
CITY OF MERIDIAN.
H. THE CONTRACTOR SHALL PROVIDE AND INSTALL STORM DRAIN
MONUMENTS TO IDENTIFY ALL STORM DRAIN MANHOLES, SEDIMENT
BOXES, DROP INLETS AND OTHER PIPE JUNCTIONS OR TERMINUSES
IN ACCORDANCE WITH ISPWC SD-623.
I. ALL STORM MANHOLES, COVERS, FRAMES, ETC., SHALL COMPLY WITH
ACHD SUPPLEMENTAL SPECIFICATIONS AND REQUIREMENTS.
J. FOR PIPES LESS THAN OR EQUAL TO 24", STANDARD MANHOLE
FRAME, COVER AND RISER PER ISPWC STANDARD DRAWING SD-611.
STORM DRAIN MANHOLES SHALL BE 48"0 MANHOLE (MINIMUM 2'
SUMP). COVER SHALL BE MARKED "STORM WATER".
K. FOR PIPES GREATER THAN 24", STANDARD MANHOLE FRAME, COVER
AND RISER PER ISPWC STANDARD DRAWING SD-613A. STORM DRAIN
MANHOLES SHALL BE 72"0 MANHOLE (MINIMUM 2' SUMP). COVER
SHALL BE MARKED "STORM WATER".
NOTE: SEAL -ENGINEER BENCHMARK: SHEET NO
WORK CONTAINED WITHIN THESE PLANS S51oNALe CITY OF MERIDIAN, ID
SHALL NOT COMMENCE UNTIL AN F� •PLANNING C5.0
Know wharsbelow. ENCROACHMENT PERMIT AND/OR A Q�0�15TfgF0 B gLAINE A. WOMER •SURVEYING SEE SHEET WOODCREST TOWNHOMES SUBDIVISION
GRADING PERMIT HAS BEEN ISSUED, CIVIL C1.0
Call before you dig No. 17011 CIVIL ENGINEERING ENGINEERING STORM WATER IMPROVEMENT PLANS FILE NO.
.PUBLIC woxxs RETENTION POND AND SEEPAGE BED DETAILS
DRAWING STATUS 9y9TF �oP�� N1420004
FOR AGENCY REVIEW MARK BY DATE APPR, DATE �pE FF ��� Boise, ID 83706, 4355 M E-.1d St-t, Suite 145 . 1-208-593-7555 SCALE:
ENGINEER REVISIONS COUNTY W N H: V: