City of Orlando Little Lake Fairview Restoration
Transcription
City of Orlando Little Lake Fairview Restoration
DOING (MUCH) MORE WITH LESS City of Orlando Little Lake Fairview Restoration Performance Three Years After Construction FSA 2011 Annual Conference June 8‐10, 2011 Presenter: James Wittig, P.E., CDM Significant Contributions by Jane M. Williams, P.E., CFM, CDM and Beth K. Whikehart, P.E., CDM Project Study Area Lake Fairview Little Lake Fairview Dubsdread Golf Course Project Design Objectives • Golf course renovation • Stormwater retrofit and treatment • Wetland rehydration • Stormwater harvesting for irrigation How did we do? Little Lake Fairview Historic Dubsdread Golf Course • Designed in 1923 • Site of the Orlando Open in the 1940s • Played by such legends as Ben Hogan and Sam Snead • City of Orlando purchased in 1977 The Old Dubsdread Golf Course Grand Re‐Opening Ceremony July 10, 2008 The New and Improved Dubsdread Golf Course Improved Grading has Increased Aesthetics and Playability of the Course Pre-project Post-project Dubsdread Golf Course – Before Renovation Pond 15 Dubsdread Golf Course – After Renovation The Driving Range has Become a Stormwater Treatment Facility Pre-project New Aqua Range Dubsdread Golf Course Performance • Increase in revenue • Increase in play • Positive feedback from community • Winner of ING Honors in Golf Course Architecture category Stormwater Retrofit and Treatment Minnesota Ditch Edgewater Ditch DW Pre‐project Water Features Minnesota Ditch Edgewater Ditch Post‐project Water Features Improved Water Quality of Recharge of Drainage Well Pre-project Condition Post-project Condition Interconnected Design Improves Drainage and Treatment Stormwater Improvements Result in Reduced Pollutant Loading to Little Lake Fairview • Pollutant load reductions – 952 lbs of total nitrogen – 243 lbs of total phosphorus Little Lake Fairview Project Provides Many Water Quality Benefits • • • • Improved stormwater treatment through design Additional filtering by wetlands Improved water quality of discharge to Little Lake Fairview Improved quality of aquifer recharge Stormwater Improvements Result in Reduced Pollutant Loading to Little Lake Fairview Lake Total Nitrogen Level 2007 ‐ 2011 1.20 0.80 0.60 0.40 Project Construction 0.20 Date Dec‐10 Oct‐10 Aug‐10 Jun‐10 Apr‐10 Feb‐10 Dec‐09 Oct‐09 Aug‐09 Jun‐09 Apr‐09 Feb‐09 Dec‐08 Oct‐08 Aug‐08 Jun‐08 Apr‐08 Feb‐08 Dec‐07 Oct‐07 Aug‐07 Jun‐07 Apr‐07 0.00 Feb‐07 Total Nitrogen (mg/L) 1.00 Stormwater Improvements Result in Reduced Pollutant Loading to Little Lake Fairview (cont.) Lake Total Phosphorus Level 2007 ‐ 2011 0.020 0.015 0.010 Project Construction 0.005 Date Dec‐10 Oct‐10 Aug‐10 Jun‐10 Apr‐10 Feb‐10 Dec‐09 Oct‐09 Aug‐09 Jun‐09 Apr‐09 Feb‐09 Dec‐08 Oct‐08 Aug‐08 Jun‐08 Apr‐08 Feb‐08 Dec‐07 Oct‐07 Aug‐07 Jun‐07 Apr‐07 0.000 Feb‐07 Total Phosphorus (mg/L) 0.025 Stormwater Improvements Result in Reduced Pollutant Loading to Little Lake Fairview (cont.) Lake Trophic State Index 2007 ‐ 2011 100.00 90.00 Hypereutrophic 70.00 60.00 50.00 Eutrophic Mesotrophic Oligotrophic 40.00 30.00 20.00 Project Construction 10.00 Date Dec‐10 Oct‐10 Aug‐10 Jun‐10 Apr‐10 Feb‐10 Dec‐09 Oct‐09 Aug‐09 Jun‐09 Apr‐09 Feb‐09 Dec‐08 Oct‐08 Aug‐08 Jun‐08 Apr‐08 Feb‐08 Dec‐07 Oct‐07 Aug‐07 Jun‐07 Apr‐07 0.00 Feb‐07 Trophic State Index 80.00 Wetland Rehydration • Benefits: Water quality improvement, restores hydroperiod, promotes a healthy habitat Little Lake Fairview PZ-1 PZ-2 DW Wetland Boundaries Wetland Disconnected From Drainage Well Pre-project Condition Post-project Condition Little Lake Fairview Wetland Hydration Wetland Rehydration • Multiple pond overflows send treated stormwater to the adjacent wetland Wetland Monitoring • Wetland water levels were monitored for more than five years Wetland Rehydration • Wetland water levels measured at Piezometer PZ‐1 91.50 91.00 Pre‐Construction Average Stage = 87.94 Post‐Construction Average Stage = 88.85 90.50 Wetland Water Elevation (ft NAVD) 90.00 89.50 89.00 88.50 88.00 87.50 87.00 86.50 86.00 Jan-04 Construction May-05 Oct-06 Feb-08 Date Jul-09 Nov-10 Water Conservation Through Stormwater Harvesting Golf Course Irrigation Parameters Pre‐project • 55 acres of irrigatable area • Two groundwater wells provide all irrigation Post‐project • 72 acres of irrigatable area • Stormwater system is primary irrigation source • Groundwater wells are back‐up source • Pump station pumps from Pond 15 to irrigation system Stormwater Harvesting Components • 1300‐gpm irrigation pump station Stormwater Harvesting Components • Pond 15 acts as a very large wet well • 1 inch of rainfall results in 6 to 8 inches of rise in Pond 15 Pond 15 Stormwater Harvesting System Operations • When Pond 15 falls 1 foot below NWL GW pumps kick on to supplement pond • Back up GW pumps turn off before surface water flow from Pond 15 New Golf Course Irrigation System Constructed Stormwater Harvesting System Operations • Pumps computer automated • Operates 3‐4 times per week • Runs for 6.5 hours per cycle • Typically turns on at 10:30 pm • Puts out 400,000 gallons per cycle Water Conservation Through Stormwater Harvesting Total Water Use for Golf Course Irrigation 2001 ‐ 2010 140.0 Annual Total Water Use (MG) groundwater 120.0 stormwater 100.0 80.0 60.0 40.0 20.0 No Data 0.0 2001 2002 2003 2004 2005 Year 2006 2007 2008 2009 2010 Water Conservation Through Stormwater Harvesting (cont.) 120.0 Groundwater Use for Golf Course Irrigation 2001 ‐ 2010 Annual Groundwater Use (MG) Grow‐in period 100.0 After Construction Before Construction 80.0 60.0 40.0 20.0 No Data 0.0 2001 2002 2003 2004 2005 2006 Year 2007 2008 2009 2010 Actual Water Use Versus Permitted and Estimated Water Use Golf Course Irrigatable Acreage Total Max Allowable (MG) Groundwater Max Allowable (MG) Previous Permit (1997 CUP) 55 56.34 56.34 Prior to construction Current Permit (2008 CUP) 72 69.60 51.41 After construction Source Comment Actual Water Usage (average rainfall) 72 55.90 10.80 Actual CUP reporting (2009 and 2010) Estimated Water Usage (average rainfall) 72 56.14 36.73 Estimated for permitting Project Partners St. Johns River Water Management District Neighborhood Association Group Diocese of Orlando City of Orlando FDOT FDEP Dubsdread Golf Course Thank you!