A Groundwater Recharge Plan for an Abandoned Quarry
A Groundwater Recharge Plan for an Abandoned Quarry A Groundwater Recharge Plan for an Abandoned Quarry
A Groundwater Recharge Plan for an Abandoned Quarry Raymond K. Will Edwin Lin Annual Meeting and International Conference - Integrated Watershed Management April 22 - 25, 2007 Todd Engineers 2200 Powell Street, Suite 225, Emeryville, CA
- Page 2 and 3: Groundwater Recharge Plan Objective
- Page 4 and 5: Headquarters, Alamitos Percolation
- Page 6 and 7: Aerial View Todd Engineers
- Page 8 and 9: Site Investigation Groundwater inve
- Page 10 and 11: Map Todd Engineers
- Page 12 and 13: Development Site Plan Undisturbed f
- Page 14 and 15: Infiltration Trenches and Test Site
- Page 16 and 17: Infiltrometer Results 30 Infiltrome
- Page 18 and 19: Groundwater Recharge - Existing Con
- Page 20 and 21: Net Impact of Project on Groundwate
- Page 22 and 23: Detention/Recharge Facility Design
- Page 24 and 25: Conclusions Installation of a sub-g
A <strong>Groundwater</strong> <strong>Recharge</strong> <strong>Pl<strong>an</strong></strong> <strong>for</strong><br />
<strong>an</strong> Ab<strong>an</strong>doned <strong>Quarry</strong><br />
Raymond K. Will<br />
Edwin Lin<br />
Annual Meeting <strong>an</strong>d<br />
International Conference -<br />
Integrated Watershed M<strong>an</strong>agement<br />
April 22 - 25, 2007<br />
Todd Engineers<br />
2200 Powell Street, Suite 225, Emeryville, CA
<strong>Groundwater</strong> <strong>Recharge</strong> <strong>Pl<strong>an</strong></strong><br />
Objective<br />
Background<br />
Site Investigation<br />
Evaluation of Alternatives<br />
Design<br />
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Objective<br />
Convert s<strong>an</strong>d <strong>an</strong>d gravel quarry to mixed<br />
residential <strong>an</strong>d commercial complex<br />
Maximize onsite stormwater infiltration<br />
Mitigate impact of development on water<br />
resources<br />
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Headquarters,<br />
Alamitos Percolation Ponds<br />
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<strong>Quarry</strong> Site - Bergstrom Pit<br />
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Aerial View<br />
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Background<br />
Location in City of Scotts Valley, Cali<strong>for</strong>nia<br />
S<strong>an</strong>d <strong>an</strong>d gravel quarry overlying S<strong>an</strong>ta<br />
Margarita S<strong>an</strong>dstone<br />
Aquifer <strong>for</strong> local drinking water supply wells<br />
Difficult building site<br />
Development not allowed to increase existing<br />
peak stormwater discharge rate<br />
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Site Investigation<br />
<strong>Groundwater</strong> investigations - test wells<br />
Hydrogeologic mapping<br />
<strong>Recharge</strong> to replenish aquifer<br />
Watershed area<br />
Infiltration tests<br />
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Hydrogeologic Cross Section<br />
900<br />
800<br />
A<br />
Purisima<br />
Formation<br />
Bergstrom<br />
Pit<br />
A'<br />
700<br />
S<strong>an</strong>ta Cruz<br />
Mudstone<br />
Bergstrom Pit<br />
Carbonera Creek<br />
El Pueblo<br />
Well Field<br />
Purisima<br />
Formation<br />
600<br />
S<strong>an</strong>ta Margarita<br />
S<strong>an</strong>dstone<br />
Alluvium<br />
S<strong>an</strong>ta Cruz<br />
Mudstone<br />
500<br />
400<br />
300<br />
Monterey<br />
Formation<br />
200<br />
100<br />
Gr<strong>an</strong>ite<br />
100<br />
0<br />
Lompico<br />
S<strong>an</strong>dstone<br />
0<br />
0 500<br />
Scale in Feet<br />
0 1,000 2,000<br />
3,000 4,000 5,000 6,000 7,000<br />
Dist<strong>an</strong>ce (feet)<br />
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Map<br />
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Infiltration Tests<br />
Site pl<strong>an</strong><br />
Site constraints <strong>for</strong> infiltration tests <strong>an</strong>d<br />
detention/recharge facility<br />
Exploration trenches <strong>an</strong>d infiltrometer test locations<br />
Infiltrometer design<br />
Infiltrometer results<br />
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Development Site <strong>Pl<strong>an</strong></strong><br />
Undisturbed<br />
<strong>for</strong>ested l<strong>an</strong>d<br />
Modified slope<br />
Undisturbed<br />
<strong>for</strong>ested<br />
l<strong>an</strong>d<br />
Irrigated l<strong>an</strong>dscape /<br />
Impervious surfaces<br />
Map Source: Ruggeri-Jensen Azar & Associates<br />
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Storm Drain Schematic<br />
Retention/<strong>Recharge</strong> Facility<br />
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Infiltration Trenches <strong>an</strong>d Test Sites<br />
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Infiltrometer Design<br />
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Infiltrometer Results<br />
30<br />
Infiltrometer 1<br />
25<br />
Infiltrometer 2<br />
Infiltrometer 3<br />
20<br />
15<br />
10<br />
5<br />
0<br />
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14<br />
Time (days)<br />
Note: Infilltration rate <strong>for</strong> Infiltromters 1 <strong>an</strong>d 3 calculated using open ring surface area (7.06 sq. ft.)<br />
Infiltration rate <strong>for</strong> Infiltrometer 2 calculated using entire pit bottom surface area (36 sq. ft.)<br />
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Water Bal<strong>an</strong>ce<br />
P - R0 - (SM1 - SM2) - AET = R<br />
P = precipitation<br />
R0 = runoff<br />
SM1 = soil moisture start of month<br />
SM2 = soil moisture end of month<br />
AET = actual evapotr<strong>an</strong>spiration<br />
R = groundwater recharge<br />
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<strong>Groundwater</strong> <strong>Recharge</strong> -<br />
Existing Conditions<br />
Water Year<br />
(Oct-Sep)<br />
Precipitation<br />
(inches)<br />
<strong>Groundwater</strong> <strong>Recharge</strong> <strong>for</strong> Existing Conditions<br />
Individual Site Water Bal<strong>an</strong>ces Captured Runoff Total Gw <strong>Recharge</strong><br />
Forested Undeveloped Forested Existing<br />
L<strong>an</strong>d Bare Soil L<strong>an</strong>d Conditions<br />
(AFY) (AFY) (AFY) (AFY)<br />
1990 - 1991 26.64 3.9 6.9 3.1 14.0<br />
1991 - 1992 33.55 5.1 8.3 4.0 17.4<br />
1992 - 1993 50.06 15.7 14.6 5.9 36.2<br />
1993 - 1994 27.81 0.7 5.6 3.3 9.6<br />
1994 - 1995 58.73 20.1 18.2 6.9 45.2<br />
1995 - 1996 47.08 11.7 13.1 5.6 30.4<br />
1996 - 1997 47.67 16.5 14.8 5.6 36.9<br />
1997 - 1998 63.74 22.6 19.8 7.5 49.9<br />
1998 - 1999 40.66 8.9 11.1 4.8 24.8<br />
1999 - 2000 49.41 15.0 14.3 5.8 35.1<br />
2000 - 2001 33.74 2.3 7.7 4.0 14.0<br />
2001 - 2002 41.30 10.2 11.9 4.9 26.9<br />
2002 - 2003 42.45 8.0 11.5 5.0 24.5<br />
2003 - 2004 37.04 11.0 11.7 4.4 27.1<br />
2004 - 2005 57.35 15.6 16.3 6.8 38.6<br />
Minimum<br />
Maximum<br />
15-Year Ave<br />
26.64 0.7 5.6 3.1 9.6<br />
63.74 22.6 19.8 7.5 49.9<br />
43.82 11.1 12.4 5.2 28.7<br />
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<strong>Groundwater</strong> <strong>Recharge</strong> -<br />
Post-Development Conditions<br />
Water Year<br />
(Oct-Sep)<br />
Precipitation<br />
(inches)<br />
Individual Site Water Bal<strong>an</strong>ces Captured Runoff in Detention Facility Detention Total Gw <strong>Recharge</strong><br />
Forested Modified Irrigated Modified Irrigated Pavement Facility Post-Development<br />
L<strong>an</strong>d Slopes L<strong>an</strong>dscape Slopes L<strong>an</strong>dscape Roof Overflow Conditions<br />
(AFY) (AFY) (AFY) (AFY) (AFY) (AFY) (AFY) (AFY)<br />
1990 - 1991 26.64 1.8 4.1 2.9 3.2 0.7 11.2 0.0 23.8<br />
1991 - 1992 33.55 2.3 4.8 2.7 4.0 0.9 14.1 0.0 28.7<br />
1992 - 1993 50.06 7.2 10.5 5.5 5.9 1.3 21.0 0.0 51.5<br />
1993 - 1994 27.81 0.3 2.4 2.0 3.3 0.7 11.7 0.0 20.4<br />
1994 - 1995 58.73 9.2 12.9 6.2 7.0 1.5 24.7 0.0 61.5<br />
1995 - 1996 47.08 5.7 8.8 4.7 5.6 1.2 19.8 -1.5 44.3<br />
1996 - 1997 47.67 7.5 10.9 5.9 5.7 1.3 20.0 -0.6 50.7<br />
1997 - 1998 63.74 10.3 14.2 6.6 7.6 1.7 26.8 0.0 67.2<br />
1998 - 1999 40.66 4.1 6.8 3.6 4.8 1.1 17.1 -0.5 36.9<br />
1999 - 2000 49.41 6.8 10.1 5.2 5.9 1.3 20.8 -1.1 49.0<br />
2000 - 2001 33.74 1.1 3.3 2.1 4.0 0.9 14.2 0.0 25.5<br />
2001 - 2002 41.30 4.6 7.5 4.1 4.9 1.1 17.3 0.0 39.6<br />
2002 - 2003 42.45 3.6 6.3 3.5 5.0 1.1 17.8 -3.4 34.1<br />
2003 - 2004 37.04 5.0 8.0 4.6 4.4 1.0 15.6 -0.4 38.1<br />
2004 - 2005 57.35 7.1 10.4 4.8 6.8 1.5 24.1 0.0 54.7<br />
Minimum<br />
Maximum<br />
15-Year Ave<br />
26.64 0.3 2.4 2.0 3.2 0.7 11.2 -3.4 20.4<br />
63.74 10.3 14.2 6.6 7.6 1.7 26.8 0.0 67.2<br />
43.82 5.1 8.1 4.3 5.2 1.2 18.4 -0.5 41.7<br />
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Net Impact of Project on<br />
<strong>Groundwater</strong> <strong>Recharge</strong><br />
Total Gw <strong>Recharge</strong> Total Gw <strong>Recharge</strong><br />
Net Ch<strong>an</strong>ge in Gw<br />
Water Year Precipitation<br />
Existing<br />
Post-Development<br />
<strong>Recharge</strong><br />
(Oct-Sep) (inches)<br />
Conditions<br />
Conditions<br />
(AFY)<br />
(AFY)<br />
(AFY)<br />
1990 - 1991 26.64 14.0 23.8 9.9<br />
1991 - 1992 33.55 17.4 28.7 11.3<br />
1992 - 1993 50.06 36.2 51.5 15.3<br />
1993 - 1994 27.81 9.6 20.4 10.8<br />
1994 - 1995 58.73 45.2 61.5 16.2<br />
1995 - 1996 47.08 30.4 44.3 14.0<br />
1996 - 1997 47.67 36.9 50.7 13.8<br />
1997 - 1998 63.74 49.9 67.2 17.2<br />
1998 - 1999 40.66 24.8 36.9 12.2<br />
1999 - 2000 49.41 35.1 49.0 13.9<br />
2000 - 2001 33.74 14.0 25.5 11.4<br />
2001 - 2002 41.30 26.9 39.6 12.7<br />
2002 - 2003 42.45 24.5 34.1 9.6<br />
2003 - 2004 37.04 27.1 38.1 11.0<br />
2004 - 2005 57.35 38.6 54.7 16.1<br />
Minimum<br />
Maximum<br />
15-Year Ave<br />
26.64 9.6 20.4 9.6<br />
63.74 49.9 67.2 17.2<br />
43.82 28.7 41.7 13.0<br />
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Rainfall vs. Ch<strong>an</strong>ge in <strong>Recharge</strong><br />
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Detention/<strong>Recharge</strong> Facility<br />
Design Criteria<br />
Preliminary design – detention/recharge facility<br />
Location beneath parking structure<br />
Water quality criteria<br />
Cali<strong>for</strong>nia Central Coast Regional Water Quality<br />
Control Board<br />
U.S. Environmental Protection Agency<br />
Cali<strong>for</strong>nia Stormwater Quality Association<br />
Stormwater pre-treatment chamber<br />
Design: per<strong>for</strong>ated CMP pipe in gravel filled trench<br />
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Detention Basin<br />
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Conclusions<br />
Installation of a sub-grade<br />
stormwater<br />
detention/recharge facility is technically feasible<br />
Stormwater BMPs will be incorporated<br />
Project will meet the City of Scotts Valley’s<br />
stormwater design requirements<br />
Project will satisfy Scotts Valley Water District’s<br />
goal of maximizing onsite recharge<br />
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Acknowledgements<br />
City of Scotts Valley<br />
Scotts Valley Water District<br />
St<strong>an</strong>dard Pacific Homes<br />
Ruggeri, Jensen, Azar & Associates<br />
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