CARY LAKE HOMEOWNERS ASSOCIATION Water Quality Issues 01-21-2014

CARY LAKE Jackson Creek Kahn Pond Storm water discharge pipes Dam & spillways (2)

North End Feb 2012 – Lake down Trenholm Rd. Roper Pond & Arcadia Edge Apartments Dent Middle School Silt delta Kahn pond Decker Blvd. Old Zorba’s Restaurant Jackson Creek O’Neil New Magistrates Courts 2014 New Elementary School 2014

New Threats – RSCD2 elementary School, Magistrates Courts on Decker, Cardinal Newman School & other construction

Cardinal Newman Site

Cardinal Newman – Absence of Buffer

Richland Elementary Site

New Magistrates Courts on Decker

Vacant Lots on Cary Lake

Siltation Threats North End Cardinal Newman New Elementary School 2014 – 2015 3. New Magistrates Courts on Decker 2014 4. Kahn Pond 5. Six Storm water discharge pipes South end 6. Siltation Mounds from Trenholm 7. Potential for development of 12 acres

Do Private Lakes Provide a Public Benefit ? Capture storm water run-off Reservoir for intense rain events Repository for silt, trash & pollution Attract wildlife to urban areas Aesthetically pleasing to residents No cost to the public purse

What is the Reservoir Effect? Control lake level to provide reservoir for capture of intense rain events. Mitigates downstream flooding If the private lakes were not there then Richland County Storm Water Department would need to provide services for capture of storm water, silt & pollution.

RESERVOIR QUESTIONS Can the level of water in private lakes be managed to provide a “buffer” for intense rain events thereby mitigate downstream flooding? Can individual lake owners coordinate to provide a controlled level throughout the watershed Can this be achieved by suitable automatic equipment? If yes, then does this enable private lakes to apply for public financial support?

Depth Gage Installation by GCWA

Maintenance Costs Dam Fish Insurance Landscape & trees Taxes

Maintenance Addition of fish Reservoir adjustment

Big fish in Cary Lake

Cary Lake Dam

Dam Maintenance

Inside Sluice Box

Dredging 50,000 tons removed 2010 – 2011 Cost Approximately $750,000 Paid by Richland County No cost to CLHA

Kahn Pond – Fully Silted Old Zorbas Jackson Creek Old Dam Wall Kahn Pond Decker Blvd. Old Red Lobster Silt Delta Cary Lake

Kahn Pond Positions of pictures taken Mar 2013 Bar pushed to full depth into “quicksand” 5 ft long bar 5 ft long bar Bank of sand carved out by the creek

KAHN POND SILTATION 5 foot long Steel bar

North End After Dredging 2011 Creek flowing past Zorba’s and under Decker Bvd. Kahn Pond Silt After dredging 2011 Lake down - Full depth 5 – 5 ½ feet After dredging 2011 Lake down - Full depth 5 – 5 ½ feet

North End – Feb 2013 – Lake down Kahn Pond Depth 5ft Depth 3ft 6in Depth 4ft 6in After dredging 2013 Lake down - Full depth 3 ½ – 4 ½ feet

Trash behind old Zorbas on Decker

Trash in Lake after raising level

Storm water pollution Brookfield Rd Water Main burst 02-20-2013

Kahn Pond - Turbidity Boom & Trash

Kahn Pond & Boom Fourteen months old Wall of old dam in background detached from base & breaking apart Wall of old dam in background is unstable

Trenholm End Siltation

Large Siltation Mound

Lake Catherine

Lake Catherine

Lake Catherine Siltation

Siltation in Lake Catherine Serious silt after construction of I-77 Eventually dredged by DoT 1993 Completely re-silted by 2010 HoA spent $100,000 on consultants, lobbying Cost estimated at $980,000 Authorities policy not to dredge private lakes However, dredging now under consideration with cost share between County, City & FA

Lake Issues - Summary Sediment from land disturbances - RSD2 Elementary School Trenholm Extn./O’Neil - County Magistrates Courts on Decker - Commercial developments on Two Notch corridor - Potential for development of 12 acres at S. end Trash Pollution Sources - Jackson Creek - Decker & Trenholm - six storm-water pipes - a spillway under Trenholm

Summary continued Key question If the reservoir model works does it open the door for public funding for siltation control?

Conclusion Cary lake is under threat from sedimentation & pollution from storm water run-off CLHA needs professional advice CLHA Water Quality Committee has obtained quotes from four consulting organizations Strategy in the short term is to focus on monitoring construction activity to ensure that codes are enforced All cost $ & we are seeking grants

Water Quality Committee Chair – Alicia Myhrer Mark Huguley Peter Chesney Hal Thornton Karl Reinecke Debbie Robertson

Trash Pick-up

Richland Elementary Site

Quotations & Actions under Review Consultant review of siltation monitoring methods - Bathymetric survey entire lake +/- 1inch - Contours linked to sea level datum - Interface with dredging contractor drawings Conventional survey of Kahn pond with lake down Monitoring of construction discharges - 2 x private consultants - US Geological Survey Dept

Do Private Lakes Provide a Public Benefit ? Capture storm water run-off Reservoir for intense rain events Repository for silt, trash & pollution Attract wildlife to urban areas Aesthetically pleasing to residents Private lakes deserve public funding support