Village of Wilmette West Side Neighborhood Storage Stormwater - PowerPoint PPT Presentation

Village of Wilmette West Side Neighborhood Storage Stormwater Detention Vault Configuration Alternatives Matthew J. Moffitt P.E., CFM, CPESC

Title Detention Vault Configuration Alternatives West Side Neighborhood Storage • Configuration Criteria • Pumping Stations • Community Playfield Alternatives • Hibbard Park Alternatives • Thornwood Park Alternatives

Title Detention Vault Configuration Alternatives • Precast Concrete Detention Vault (not visible from the surface) • All configurations have equivalent volume and performance • Alternatives designed to minimize impact to trees • Deeper vault configurations will require pump stations

Title Underground Detention Wescott Park in Northbrook, IL

Title Pump Stations • Pump only volume below the gravity outlet • Pump rate designed to provide similar performance to gravity outlet (24-hr drawdown) • Backup pump and power included • Will require more annual maintenance

Title Pump Stations

$10,680,000 32 Trees Removed

$10,420,000 ($260,000↓) 2 Trees Removed

$9,880,000 ($800,000↓) 0 Trees Removed

Title Community Playfield Comparison Original Configuration Alt. Configuration 1 Alt. Configuration 2 $10,680,000 $10,420,000 ($260,000↓) $9,880,000 ($800,000↓) Gravity Outlet Gravity Outlet Gravity & Pumped Outlet Relocation of EX Detention Preserves EX Detention Preserves EX Detention 3.86 Acre footprint 3.56 Acre footprint 1.9 Acre footprint 6 feet Tall (underground) 6 feet Tall (underground) 11’ - 4” Tall (underground) Removal of 32 trees Removal of 2 trees Protects all trees Temp impact of 1 soccer Temp impact of 3 soccer Temp impact of 1 soccer field fields field

$7,430,000 36 Trees Removed

$6,280,000 ($1,150,000↓) 8 Trees Removed

$6,340,000 ($1,090,000↓) 8 Trees Removed

$7,180,000 ($250,000↓) 2 Trees Removed

Title Hibbard ParkComparison Original Alt. Configuration 1 Alt. Configuration 2 Alt. Configuration 3 Configuration $7,430,000 $6,280,000 $6,340,000 $7,180,000 ($1,150,000↓) ($1,090,000↓) ($250,000↓) Gravity Outlet Gravity & Pumped Gravity & Pumped Gravity & Pumped Outlet Outlet Outlet 2.0 Acre footprint 1.0 Acre footprint 1.0 Acre footprint 0.8 Acre footprint 6 feet Tall 11’ - 4” Tall 11’ - 4” Tall 15 feet Tall (underground) (underground) (underground) (underground) Removal of 36 trees Removal of 8 trees Removal of 8 trees Removal of 2 trees on east side on west side on west side Temp. disrupts 2 Temp. disrupts 1 Temp. disrupts 1 Temp. disrupts 1 baseball fields baseball field baseball field baseball field

$8,610,000 53 Trees Removed

$8,810,000 ($200,000↑) 60 Trees Removed Preserves Oak Grove

$7,060,000 ($1,550,000↓) 3 Trees Removed

Title Thornwood Park Comparison Original Configuration Alt. Configuration 1 Alt. Configuration 2 $8,610,000 $8,810,000 ($200,000) $7,060,000 ($1,550,000↓) Gravity Outlet Gravity Outlet Gravity & Pumped Outlet 3.0 Acre footprint 3.0 Acre footprint 1.4 Acre footprint 6 feet Tall (underground) 6 feet Tall (underground) 11’ - 4” Tall (underground) Removal of 53 trees Removal of 60 trees Removal of 3 trees Impacts Oak grove Preserves Oak grove Preserves Oak grove Temp impact of 2 baseball Temp impact of 2 baseball Temp impact of 2 baseball fields fields fields

Village of Wilmette West Side Neighborhood Storage Stormwater Detention Vault Configuration Alternatives Matthew J. Moffitt P.E., CFM, CPESC