New ew port N New ew s Wa ter ers hed ed Im provem em - - PowerPoint PPT Presentation

New ew port N New ew s Wa ter ers hed ed Im provem em en ents P P rovides es Wa t a ter Q Qua l a lity a n a nd T TMDL Opportuni unities

March 2 2, 2017

Intr trod

• ducti

tion

• n

What if we could enhance our Harmful Aquatic Boom (HAB) management program and develop low cost TMDL Action Plan Projects

• n 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

• City has decided to not seek

formal “certification” of credits developed at this time

• Use credits to satisfy MS4 permit

requirements by the City or joint use by neighboring MS4 partners

Certification Evaluation

• Certification Process
• Ownership
• Administrative Concerns
• Geographic Considerations
• Pending Legislation

• Overflow Capture
• Treat More Water
• Growth?
• Little Creek Treatment
• Traditional Watershed

BMPs

• Lake Management
• Dredging
• Weed Harvesting
• Aeration/Mixing
• Little Creek Usage

Reduction in Overflow Volume Indirect Reduction in Pounds to Bay in Overflow Reduction in Reservoir Concentration

x =

3) P Proje

• ject

cts

Direct Reduction in Pounds to Bay

Harwoods Mill and Lee Hall BMP Evaluation Sites

!

A

Existing BMP

!

A

Proposed BMP Waterways .

15 Facilities Costs = $50,000 - $450,000 P Removal = 1 – 67 lbs. 308 lbs. of P Removed P Efficiency = $15,000/lb.

BMP S Sites

POTENTIA IAL B BMP S Sites es

Stream Restoration

Altered Hydrograph from upstream development and forest clearing leads to erosion

Harwoods Mill and Lee Hall Stream Restoration Sites

Streams for Nutrient Credit

Ephemeral Streams Perennial Streams Proposed Stream Restorations Other Waterways

65 Streams Evaluated 33 Segments For Restoration 13.7 Miles Cost = $200/FT P Removal = 6,200 lbs. P Efficiency = $3000/lb.

.

Strea eam R Restor

• ration S

Sites es

• 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

Airport Di Ditch

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

• nversio

ion

Approved Conversion Factors Basin Land Use From Conversion To Edge of Stream Reductions TN (lbs/ac/year) Edge of Stream Reductions TP (lbs/ac/year) Edge of Stream Reductions TSS (lbs/ac/year) James Pervious Forest 5.03 0.48 57.82 York Pervious Forest 5.18 0.4 78.3 Basin Pervious to Forest Acres TN Removed lbs TN/yr TP Removed lbs TP/yr TSS Removed 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
• verflows 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 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

• 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

Chickahominy River 0.055 mg/L P Terminal Reservoirs – Lee Hall and Harwood's Mill Little Creek 0.015 mg/L P

• 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

Watershed a and Lake Management – Reduced Nutrient L Levels

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 2 facilities 650 $1,200 Dredging – Direct benefit 100 acres/ 480,000 cu yds tbd tbd Weed Harvesting – Direct Benefit Harwood's Mill – 97 acres tbd tbd Land Use Conversion 100 Acres 48 $0 In-Lake Management Reduced Lake Concentrations by .02mg/l 992 $1,000 Reduced Outfall at terminal reservoirs Reduction in freeboard by 1.5 ft 1068 $0 Little Creek Treatment 5 mgd to LC Reservoir and release or treat 610 $164/lb/yr

Reg egula latory a and P Pol

• lic

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