City of Grand Ledge Water Supply Studies Studies Overview Exis - PowerPoint PPT Presentation

City of Grand Ledge Water Supply Studies

Studies Overview • Exis istin ing ir iron removal l pla lant approachin ing end of useful l li life • Three studie ies to evaluate water supply ly repla lacement: • New iron removal treatment system • New water softening treatment system • Connection and water supply from Lansing Board of Water and Light • Compare costs of optio ions/present worth analy lysis is

Existing System • Ir Iron removal l pla lant util iliz izin ing an Aeralater. • Suppli lied by three groundwater well lls. • Exis istin ing system • Iron removal • Feed chlorine, fluoride and phosphate • Hard water

Basis of Design Projected Water Demands - Cit ity of Grand Ledge 1.9 1.74 1.67 1.65 1.7 1.5 (mgd) Demand (m 1.3 De 1.1 0.91 0.87 0.86 0.9 0.7 0.5 2005 2010 2015 2020 2025 2030 2035 2040 2045 Ye Year Historical ADD Historical MDD Projected ADD Projected MDD

Basis of Design • Pla lant capacity of 4.0 mgd id identif ifie ied by Cit ity. • This is capacit ity was used as a basis is of desig ign for studie ies.

Iron Removal • Ir Iron Removal l Treatment Objectiv ives: • Iron removal • Manganese removal • Radium removal • Study to in install ll new ir iron removal l treatment system • Repair ir of exis istin ing Aeralater • Use of exis isting treatment buil ildin ing

Iron Removal Schematic

Iron Removal Floor Plan

Iron Removal O&M Costs for the Selected Alt lternativ ive Summary ry of Project Costs O&M Cost It Items Annual Cost Cost Category ry Estimated Costs La Labor $32,400 Treatment Pla lant $8,690,000 Chemical Usage $24,000 Sitework $2,430,000 Ele lectrical Usage $41,000 Work at t Remote Sites $828,000 Total Construction Cost Opinion $11,9 ,948,0 ,000 Gas Usage $4,500 Reagents, , Standards $3,000 Pil ilot Study $75,000 Annual O&M Costs $104,9 ,900 Corr rrosion Control Study $180,000 Engineering $1,200,000 Administrative, Le Legal, , Bonding $50,000 Total Proje ject Cost $13,4 ,453,0 ,000

Wa Water Softening • Benefit its of softened water • Target of 120 mg/L • Range 100 – 140 mg/L • Current hardness ~460 mg/L • Looked at three technolo logie ies: • Reverse Osmosis Softening • Ion Exchange Softening • Lime Softening • Conventional • Pellet

Reverse Osmosis Softening • Reverse osmosis is removes alm lmost all ll dis issolv lved soli lids, in inclu ludin ing hardness components • Water forced across semi- permeable le membrane usin ing pressure • Requir ires ir iron removal l pretreatment • Ble lend water wit ith ir iron pla lant dis ischarge to meet target hardness

Reverse Osmosis Softening Pros and Cons Advantages Disadvantages • Operation can be automated • Membranes are sensitive to fouling • RO membranes can remove currently regulated • Produces a high-volume waste contaminants and have been stream, which has elevated total shown to be effective in dissolved solids prone to pipe removing unregulated scaling emerging contaminants • Additional well capacity and iron • Radium removal from removal capacity required permeate stream because of 20-25% rejection rate • High operational costs, specifically power consumption • Additional staffing will be needed. Typical Reverse Osmosis Skid

Reverse Osmosis Schematic

Reverse Osmosis Floor Plan

Reverse Osmosis Softening Costs Cost Category ry Estimated Costs O&M Cost It Items Annual Cost Treatment Pla lant $22,673,000 Ele lectrical Costs $96,000 Sitework $6,935,000 Chemical Costs $63,000 Work at t Remote Sites $657,000 Membrane Replacement $50,000 Total Construction Cost Opinion $30,2 ,265,0 ,000 Additional Staffing $300,000 Pil ilot Study $75,000 Annual O&M Costs $509,0 ,000 Corr rrosion Control Study $180,000 Engineering $3,000,000 Administrative, Le Legal, , Bonding $50,000 Total Proje ject Cost $33,5 ,570,0 ,000

Ion Exchange Softening • Io Ion Exchange removes hardness by adsorptio ion onto a resin in • Resin in must be perio iodic icall lly regenerated wit ith brin ine solu lutio ion • Requir ires ir iron removal l pretreatment • Ble lend water wit ith ir iron pla lant dis ischarge to meet target hardness

Ion Exchange Softening Pros and Cons Advantages Disadvantages • Easily expandable • Adds sodium to finished water • Simplest technology • Cost of large amounts of salt used for regeneration • Produces least volume of wastewater and sludge • Produces a highly concentrated solids waste stream • Operation can be automated • Disposal of regenerate waste water to WWTP may be • Radium removal for water undesirable passing through IX resin Typical Ion Exchange System

Ion Exchange Schematic

Ion Exchange Floor Plan

Ion Exchange Softening Costs O&M Cost It Items Annual Cost Cost Category ry Estimated Costs Ele lectrical Costs $50,000 Treatment Pla lant $14,837,000 Sitework $4,395,000 Chemical Costs $213,000 Work at t Remote Sites $657,000 Resin Replacement $20,000 Total Construction Cost Opinion $19,8 ,889,0 ,000 Additional Staffing $225,000 Pil ilot Study $75,000 Annual O&M Costs $508,0 ,000 Corr rrosion Control Study $180,000 Engineering $1,990,000 Administrative, Le Legal, , Bonding $50,000 Total Proje ject Cost $22,1 ,184,0 ,000

Lime Softening • Lim ime softening removes hardness by chemic ical l precip ipitatio ion • Removes ir iron, manganese, and radiu ium • More traditio ional l softenin ing treatment for munic icipal l appli licatio ions

Lime Softening Pros and Cons Advantages Disadvantages • Lower power requirements • High chemical dosages/usage for softening equipment and required to meet target hardness longer equipment life goal • Easier to establish water • Significant residuals production stability with respect to • Lime chemical, dust, and sludge corrosion control can be messy and labor intensive • Well known, stable • High capital and operational treatment process costs • Radium removal through • Need for additional labor due to chemical precipitation more equipment, more analytical work, more process monitoring, sludge processing, and general housekeeping Typical Lime Softening System

Lime Softening Schematic

Lime Softening Floor Plan

Lime Softening Costs Cost Category ry Estimated Costs O&M Cost It Items Annual Cost Ele lectrical Costs $74,000 Treatment Pla lant $21,857,000 Chemical Costs $209,000 Sitework $4,293,000 Work at t Remote Sites $497,000 Residuals Handling $54,000 Total Construction Cost Opinion $26,6 ,647,0 ,000 Additional Staffing $300,000 Corr rrosion Control Study $180,000 Annual O&M Costs $637,0 ,000 Pla lant Engineering Costs ts $2,900,000 Administrative, Le Legal, , Bonding $50,000 Total Proje ject Cost $29,7 ,777,0 ,000

Treatment Cost Summary Treatment Construction Engin ineering & Total l Project Annual O&M Alt lternative Cost Opinion Studies Cost Costs Ir Iron Removal $11,948,000 $1,505,000 $13,453,000 $104,900 RO Softenin ing $30,265,000 $3,305,000 $33,570,000 $509,000 IX IX Softenin ing $19,889,000 $2,295,000 $22,184,000 $508,000 Lim ime Softening $26,647,000 $3,130,000 $29,777,000 $637,000

Next Steps • LBWL Supply ly Optio ions Study comple letio ion • Present worth cost analy lysis is • In Incorporate comments from revie iew of draft studie ies and submit fin inal l reports