Wastewater Collection Options for

Lakota Beach Area Sub-Basin

Special Meeting June 27, 2001

John Bowman

Lakehaven Utility District

(253) 946-5401

Goal of Meeting

• Provide information on Wastewater Collection Options

• Provide cost estimates

• Provide information on how a project can start and what it means to the property owners

• Answer Questions

Area of Interest

DRAFT Lakota Beach AreaTotal Area: ~105 AcresProperty Area: ~80 AcresTax Lots: ~135

Wastewater Collection Options• Gravity Sewer System• Pressure Sewer System• Others (not considered viable)

–Vacuum Sewer System

–STEP, Septic Tank Effluent Pumps

–Small Diameter Gravity

•Cost Components:–Infrastructure (Utility Owned, Public Facility)

–Private Facilities (Homeowner Owned)

–Fees and Charges

Gravity Sewer System Facilities

• Typical for most areas

• 4” Gravity Side Sewer pipe from Building to 6” Sewer Stub near property line (Private Facility)

• 6” Sewer Stub pipe from property to Gravity Main in street (Public Facility)

• Gravity Main flows to the treatment plant or a Central Pump Station that moves flows over hills through pressurized-mains toward the Treatment Plant

• For Lakota Beach Area, Central Pump Station is needed

DRAFT Lakota Beach AreaGRAVITY SEWER SYSTEMPump StationGravity MainForce Main

Pressure Sewer System• Alternative Sewer System (Low Pressure <50 psi)

• Short 4” Gravity flow from Building to Small Grinder Pump, usually near building (Private Facility)

• Pressurized slurry from Pump moves through a small 1-1/4” Side Sewer (Private Facility) to an equally sized Pressure Sewer Stub near the property line (Public Facility)

• Pressurized flow continues into pressure main ( Public Facility, usually 2” to 4” in diameter) in the Right-of-Way to a Gravity System or Treatment Plant

• For Lakota Beach Area, some to Treatment Plant, some to nearby gravity

DRAFT Lakota Beach AreaPRESSURE SEWER SYSTEM

Pressure Main

Has an Option been chosen for this Area?

• NO

• Typically new developments are required to provide gravity type service where available

• Alternatives are considered based on cost on environmental issues

• A selection will have to be made once a project is proposed

Gravity Sewer System with Pump Station(for LBA)

• Pros– Most home would not have mechanical components for

the home owners to maintain (some still need to pump)

– If zoning densities increased, gravity systems typically have more inherent capacity for additional flow

– Only Central Pump Station affected by power outages (on-site generator is assumed)

Gravity Sewer System with Pump Station(for LBA)

• Cons– Generally higher cost to install in developed areas

– Gravity Mains would be installed near center of road (probably need to rebuild roads)

– Gravity Mains would be installed from 6 feet to 18 feet in depth, Pump Station about 20-25 feet deep

– More disruptive to traffic and access

– 8” Minimum Size (DOE Standard)

– About 25 homes will still need to pump to gravity main

– Pump Station must account for Inflow and Infiltration potential

Pressure Sewer System(for LBA)

• Pros– Less expensive to construct

– Pressure Mains could be installed on the side of roads (avoiding significant road work)

– Pressure Mains smaller (2”- 4”), installed at about 4 feet in depth

– No Central Pump Station

– Less disruptive to traffic and access

– Lower potential for Inflow and Infiltration

Pressure Sewer System (for LBA)

• Cons– All homes would have individual pumps to maintain

– If zoning densities increased, pressure systems typically have less inherent capacity for additional flow

– Individual home owners affected by power outages

– Size of the mains is more critical. Need to maintain a 2 f/s velocity to keep solids from settling out

Infrastructure Costs

• Gravity Sewer System– Estimated Cost: $1,860,000

• Pump Station w/Force Main

• Gravity Mains and Stubs to properties

• Road Restoration

• Pressure Sewer System– Estimated Cost: $ 568,000

• Pressure main and stubs w/restoration

Private Facility Costs• Gravity Sewer System

– Estimated Cost: $2900 (Range $2000-10,000)• Assumes 120’ of 4” pipe @ 20$/ft

• Septic Tank Abandonment @ $500

• Pressure Sewer System– Estimated Cost: $5900 (Range $4000-8000)

• Assumes 120’ of 1-1/4” pipe @ 10$/ft

• Grinder Pump installed @ $4200

• Septic Tank Abandonment @ $500

Connection Fees• Gravity Sewer System

– Estimated Cost: $2865• Capital Facility Charge $2720

• Side Sewer Permit $145

• Pressure Sewer System– Estimated Cost: $3040

• Capital Facility Charge $2720

• Side Sewer Permit $145

• Private Pump Agreement $195

How are these costs paid?• Infrastructure Costs is typically distributed equitably to

property owners by either:

• Front footage

• Per Lot

• Per Area

• or Zone and Terminus

• Private Facilities Costs belong to individual properties

• Connection Fees are uniform, unless there are more than one residential unit per property

Gravity System Pressure SystemInfrastructure 11,625$ 3,550$ Private Facilities(1) 2,900$ 5,900$ Connection fees 2,865$ 3,040$ Total 17,390$ 12,490$ (1) Will vary widely depending on site condition $2000-10,000

Based on Area Charge:

Total Infrastructure Cost / 80 Acres

and assuming a 1/2 Acre Lot

Example of Total Costs:

Gravity System Pressure SystemInfrastructure 13,778$ 4,207$ Private Facilities(1) 2,900$ 5,900$ Connection fees 2,865$ 3,040$ Total 19,543$ 13,147$ (1) Will vary widely depending on site condition $2000-10,000

Based on Per Lot Charge:

Total Infrastructure Cost / 135 Lots

Example of Total Costs:

How is a Project Started?

• Utility Local Improvement District (ULID)– Petition– Resolution (special circumstances)

• Developer Extension

• Utility Project

ULID• One or more customers express interest for

sewers in a particular area

• IF there appears to be sufficient interest (51% or more by land ownership), petitions are prepared (estimated costs)

• IF the minimum of 51% of the land owner sign in favor of the formation, the Board may Certify the petitions and authorize preliminary design

ULID (continued)• Formation Hearing (new cost estimates and

boundaries may be redefined as a result)

• IF there is still support for the ULID, the Board can certify the ULID formation (Protest can still be filed)

• Project is designed and Bid - ONLY PUBLIC FACILITIES

• Financing will be reviewed (new cost estimates) and Construction begins

ULID (continued)• Final Costs are known and assessed

• Assessment Roll Hearing (Protest can be filed and allocation method can be revised)

• Legal notice of Assessment (appealable through supreme court)

• Assessments filed with County Treasurer for collections

• Assessments begin one year later and continue for 20 year

ULID (continued)• Once Public Facilities are in place, Billing

for Sewer service begin, every two months (regardless of whether properties have connected)

• Time Frame for ULID Process– Past experience: 1-1/2 to 3 years– Pressure Option may be on the shorter side– Gravity Option maybe on the longer side

Annual Assessment: Gravity Pressure

Principal 1/20 Interest Amount Principal 1/20 Interest Amount Year Balance* Principal 6% Due Year Balance* Principal 6% Due

1 $14,345 $717 $861 $1,578 1 $6,270 $314 $376 $6902 $13,628 $717 $818 $1,535 2 $5,957 $314 $357 $6713 $12,911 $717 $775 $1,492 3 $5,643 $314 $339 $6524 $12,193 $717 $732 $1,449 4 $5,330 $314 $320 $6335 $11,476 $717 $689 $1,406 5 $5,016 $314 $301 $6146 $10,759 $717 $646 $1,363 6 $4,703 $314 $282 $5967 $10,042 $717 $602 $1,320 7 $4,389 $314 $263 $5778 $9,324 $717 $559 $1,277 8 $4,076 $314 $245 $5589 $8,607 $717 $516 $1,234 9 $3,762 $314 $226 $53910 $7,890 $717 $473 $1,191 10 $3,449 $314 $207 $52011 $7,173 $717 $430 $1,148 11 $3,135 $314 $188 $50212 $6,455 $717 $387 $1,105 12 $2,822 $314 $169 $48313 $5,738 $717 $344 $1,062 13 $2,508 $314 $150 $46414 $5,021 $717 $301 $1,018 14 $2,195 $314 $132 $44515 $4,304 $717 $258 $975 15 $1,881 $314 $113 $42616 $3,586 $717 $215 $932 16 $1,568 $314 $94 $40817 $2,869 $717 $172 $889 17 $1,254 $314 $75 $38918 $2,152 $717 $129 $846 18 $941 $314 $56 $37019 $1,435 $717 $86 $803 19 $627 $314 $38 $35120 $717 $717 $43 $760 20 $314 $314 $19 $332

* Includes Capital Facilities Charge of $2720

Examples of Financing Costs (ULID Assessments):

Based on Per Area Charge:

Year Items Gravity Pressure0 Sewer Bills (1) 62$ 62$ 1 Infrastructure (2) 1,578$ 690$ ? Private Facilities(3) 2,900$ 5,900$ ? Connection fees (4) 145$ 340$

Total 4,685$ 6,992$ (1) $10.38/month or $20.76 bi-monthly (Base Charge Only). Usage fee applies

after connection @ $1.61/ccf of winter water use, typically 16 ccf (2-month)

(2) Decreasing Assessments for 20 years (Includes CFC as part of assesment).

(3) Timing Determined by property owner, cost can vary ($2000-$10,000).

(4) Paid at Time of connection

Based on Area Charge And ULID Financing:

Total Infrastructure Cost / 80 Acres

and assuming a 1/2 Acre Lot

Examples of Initial Costs:

Developer Extension• If a large property subdivides to sufficient density

to preclude septic system and needs sewer, the development could build a portion of the infrastructure.

• Latecomer Charges could be allocated to neighboring properties for the portion of the infrastructure that would benefit them

• Latecomer Charges are paid at the time of connection

Utility Project• If there is benefit to the District as a whole to

install sewers in advance, the District could do so.• Not typical• Examples:

– Financial - increase customer base– Environmental benefits– Opportunity costs (minimize future installation costs)

• prior to new road

• combination with other projects

Area of Interest

DRAFT Lakota Beach AreaTotal Area: ~105 AcresProperty Area: ~80 AcresTax Lots: ~135