New ew port N New ew s Wa ter ers hed ed Im provem em en ents P P rovides es Wa a t ter Q Qua a l lity a a n nd T TMDL Opportuni unities March 2 2, 2017
Intr trod oducti tion on What if we could enhance our Harmful Aquatic Boom (HAB) management program and develop low cost TMDL Action Plan Projects on watershed properties. AND… Partner with other municipalities and permittees offering them low cost opportunities to greatly reduce their costs
Goals ls • Assess Market • Evaluate Credit Certification Program and Trading Requirements • Opportunities • Watershed Lands • Facilities • Operations (Focus on Innovative Strategies) • Provide Recommendations for moving forward
1) M Market a and nd P Poten ential N Need eds s (Ol Older er N Num umber ers) Needs May be in Excess of 10,000 lbs P • City of Newport News - 3,265 lbs P (WIP II) • City of Hampton – 4,000 lbs P (WIP II) • York County – 500 lbs P (TMDL Action Plan) • City of Williamsburg 180 lbs (TMDL Action Plan) • VDOT – Lower Penninsula (Estimate in excess of 1,000 lbs) • Separate, Individual Industrial Stormwater permitted facilities, VPDES permits, and Federal Facilities - Large list Costs –From 260 projects submitted for SLAF - $44,000/lb P
2) Cr Credit Ce Cert rtification a and U Use Certification Evaluation • City has decided to not seek • Certification Process formal “certification” of credits Ownership • developed at this time • Administrative Concerns • Geographic Considerations • Use credits to satisfy MS4 permit Pending Legislation • requirements by the City or joint use by neighboring MS4 partners
3) P Proje oject cts Indirect Reduction Reduction in Reduction in x in Pounds to Bay in = Reservoir Overflow Overflow Concentration Volume Direct Reduction • Overflow Capture • Traditional Watershed BMPs in Pounds to Bay • Treat More Water • Lake Management Growth? Dredging Weed Harvesting Little Creek Treatment Aeration/Mixing Little Creek Usage
BMP S Sites POTENTIA IAL B BMP S Sites es 15 Facilities Costs = $50,000 - $450,000 P Removal = 1 – 67 lbs. 308 lbs. of P Removed P Efficiency = $15,000/lb . Harwoods Mill and Lee Hall BMP Evaluation Sites A Waterways . ! Existing BMP A ! Proposed BMP
Stream Restoration Altered Hydrograph from upstream development and forest clearing leads to erosion
Strea eam R Restor oration S Sites es 65 Streams Evaluated 33 Segments For Restoration 13.7 Miles Cost = $200/FT P Removal = 6,200 lbs. P Efficiency = $3000/lb . Harwoods Mill and Lee Hall Stream Restoration Sites Streams for Nutrient Credit . Ephemeral Streams Perennial Streams Proposed Stream Restorations Other Waterways
Airport Di Ditch • Loadings in Excess of 650 lbs./year of P Due to Large Bank Sloughs • Costs Estimated at Approximately $750,000 or $1200/Lb. • DEQ approvals for Innovative Measures my be required
Dr Dredging • Legislative Approval of Sediment Dredging? • Same Benefits as Street Sweeping? • 100 Acres 484,000 yards 407,722 Tons 489,266 lbs. P • Dredging Costs = $18,689,000 = $38/lb. P
Aquatic W Weed Ha Harvesting • Harvesting as Stand Alone BMP Requires DEQ Approval • Harwoods Mill • 97 Acres 842,000 lbs. 197 lbs. P • Annual Harvesting Costs = $118,000 • Cost/lb. P Removal = $560/lb. P
La Land U Use e Con onversio ion Approved Conversion Factors Edge of Edge of Edge of Stream Stream Stream Land Use Conversion Basin Reductions Reductions Reductions From To TN (lbs/ac/year) TP TSS (lbs/ac/year) (lbs/ac/year) James Pervious Forest 5.03 0.48 57.82 York Pervious Forest 5.18 0.4 78.3 Pervious to TN TSS TP Removed Basin Forest Removed Removed lbs TP/yr Acres lbs TN/yr lbs TSS/yr James 25 125.75 12 1445.5 York 25 129.5 10 1957.5
Overflow R Redu duction • Operate at a reduced freeboard to capture overflows from larger storm events • Calculated as a reduction in overflow volume • Calculated as an increase in system efficiency similar to “runoff reduction BMP efficiency increase” Additional Lbs P removed Freeboard (ft) HM LH Total 0.5 0 0 0 1 232 335 567 1.5 408 660 1068 2 526 851 1377 Assumed operations at 0.5 ft freeboard
Little C Creek eek P Pump Ov Over er Terminal Reservoirs – Lee Chickahominy Hall and Harwood's Mill River 0.055 mg/L P Little Creek 0.015 mg/L P • 5 mgd in @ 0.055 mg/L 2.29 lbs./day 838 lbs./year • 5 mgd out @ 0.015 mg/L 0.063 lbs./day 228 lbs./year • 610 lbs./year @ $100,000 Annual Pumping Costs $164/lb./year
Watershed a and Lake Management – Reduced Nutrient L Levels • Secondary Benefits of P Removal • Reduced P Concentrations in Lake • Reduced Carbon in Water Column • Reduced Treatment Costs • HAB Management Program Historic Use Data Chickahominy Pump over – 10.3 mgd Watershed Runoff – 49.8 mgd Intakes – 41 mgd Spillage/Overflow – 19.1 mgd At 0.030 mg/l – Bay Loading = 1487 lbs. At 0.020 mg/l – Bay Loading = 991 lbs. Reduction of 496 lbs. At 0.010 mg/l – Bay Loading = 495 lbs. Reduction of 992 lbs
Summa mary – Ov Over er 10, 0,000 l lbs s P Redu duction I Ide dentified ed Opportunity Description/ Units P removal (LBS) Costs per Pound Traditional BMPs 15 Facilities 308 $10,000 Stream restoration 13.7Miles Identified 6200 $3,000 Airport Ditch 6,000 ft ditch 650 $1,200 2 facilities Dredging – Direct 100 acres/ 480,000 cu yds tbd tbd benefit Weed Harvesting – Harwood's Mill – 97 acres tbd tbd Direct Benefit Land Use Conversion 100 Acres 48 $0 In-Lake Management Reduced Lake Concentrations by 992 $1,000 .02mg/l Reduced Outfall at Reduction in freeboard by 1.5 ft 1068 $0 terminal reservoirs Little Creek Treatment 5 mgd to LC Reservoir and 610 $164/lb/yr release or treat
Reg egula latory a and P Pol olic icy I Issues es • Regulated vs. Non-Regulated Land Treated • Clearing House Approval of Strategies/BMPs vs. Permit Approval by DEQ • Approval Process for Non-Approved Strategies • Do Reservoirs = Bay Tributary – To date - YES • Geographic Issues – Basin of Credit Generation
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