Storm Water Utility Improvements

Transcription

1 Storm Water Utility Improvements Overview: The Storm Water Utility includes culverts, intakes, and subsurface piping designed to convey storm water from the City during wet weather events. Status of Storm Water Utility Infrastructure: Storm Water Collection System o Areas of street flooding in localized areas due to absence of existing storm water infrastructure o Areas of street flooding in localized areas due to hydraulically overwhelmed storm water infrastructure Proposed Improvements: Following solicitation and review of citizen surveys, conducting public information meetings, and evaluation of the storm water collection system, improvements were identified and a capital improvement plan was developed to address system deficiencies. Improvements which the City has proposed to move forward with include construction of: storm water intakes, larger capacity storm sewer collection mains, and secondary storm sewers. Specifically these projects include: Lynne Drive and South 14 th Street Storm Sewer Improvements South 11 th Street Storm Sewer Improvements Horse N Buggy Secondary Storm Sewer Improvements Pleasant Street Secondary Storm Sewer Improvements

2 Sanitary Sewer Utility Improvements Overview: The Sewer Utility includes sanitary sewers, pumping stations, and the wastewater treatment facility. Due to recent regulatory changes, the City received a new wastewater discharge (NPDES) permit in late 2014, which requires compliance with the Iowa Nutrient Reduction Strategy. Status of Sewer Utility Infrastructure: Sanitary Collection System o Localized areas of the sewer system are hydraulically overwhelmed which can lead to basement backups Wastewater Treatment Facility o Existing facility not capable of achieving nutrient reduction requirements o No backup power supply o Existing facility hydraulically overloaded due to inflow and infiltration Proposed Improvements: After evaluation of the sewer utility system, improvements were identified and a capital improvement plan was developed to address system deficiencies. Improvements which the City has proposed to move forward with include: sewer main hydraulic capacity improvements to address areas of sewer overflows (basement backups), extension of sewer service to the East Annex Area, and a new mechanical wastewater treatment facility to achieve regulatory compliance.

3 Water Utility Improvements Overview: The Water Utility includes the raw water source wells, treatment plant, and distribution system (water mains, storage facilities, booster stations) designed to provide delivery of drinking water to the citizens and businesses of the City. Status of Water Utility Infrastructure: Raw Water Wells o Existing wells are at or near the end of their serviceable life (34-48 years old) o Existing raw water transmission main has history of leaks and existing route has 5 river crossings o No existing backup power supply Treatment System o Water treatment system is near the end of serviceable life (45 years old) Recent process equipment failures o No backup power supply o System demands are approaching the operational capacity of the treatment plant Distribution System o Old water mains with history of main breaks and loss of service o No station redundancy or back-up power supply for distribution system pumping Proposed Improvements: After evaluation of the water system, improvements were identified and a capital improvement plan was developed to address system deficiencies. Improvements which the City has proposed to move forward with include: new water supply wells (2), new raw water transmission main, new water treatment facility, water main replacement projects, and booster pumping facility redundancy and back-up power supply improvements. Specifically, these projects include: Alluvial Well 5 & 6 Raw Water Transmission Main New Water Treatment Plant South 14 th Street Booster Pump Station South High Pressure Zone Booster Pump Station Rapids Street Main Replacement HWY 169/Bryan St. Main Replacement

4 Project Financing Considerations Project Financing Alternatives: Multiple financing methods were evaluated to determine the best method of financing the proposed improvements. Through this evaluation, the USDA-Rural Development Water & Waste Disposal Loan & Grant program was determined to provide the most advantageous source for financing due to: Term Length Up to 40 years Low Fixed Interest Rates 2.00% % Potential to receive Grant Funds to help offset project costs Proposed Utility Rate Increases Overview: To meet debt service requirements of the proposed improvements, the implementation of a debt service charge for each utility has been proposed. To offset costs of utility operations and maintenance, rates are charged on a unit cost basis and are expected to have minimal future increases (~3% / year). It should be noted that existing and new customers alike pay for water, sewer, and storm water utility services. Additional future rate increases will be necessary to meet the modeled debt obligations. It is planned to evaluate revenues and expenditures to identify future rate adjustments as necessary. Proposed Debt Service Fee Fiscal Year Storm Water Sanitary Water Combined $ - $ - $ - $ $ 3.00 $ 7.00 $ 5.00 $ $ 3.00 $ 5.00 $ 7.00 $ $ - $ 3.00 $ $ Total $ 6.00 $ $ $ Graphs on the following pages show costs for water, sewer and storm water utility services for communities in the Des Moines metropolitan area. The graphs reflect current costs of services for a typical residential customer who uses 5,000 gallons of water and sewer service per month, and pays the typical residential storm water utility fee.

5 Monthly Residential Stormwater Fees $14.00 $12.00 $11.50 $10.00 $9.60 $9.40 $8.00 $6.00 $4.00 $2.00 $- Des Moines Adel Adel Norwalk Adel Grimes Panora Urbandale Clive Waukee Johnston Ankeny Windsor Heights Altoona West Des Moines Bondurant Pleasant Hill Adel - Current Indianola $7.50 $6.20 $6.08 $6.00 $6.00 $5.99 $5.75 $5.55 $5.50 $5.25 $5.00 $4.25 $3.25 $3.00 $3.00 $2.00

6 Monthly Residential Sewer Fees for 5000 gallon User $60.00 $50.00 $40.00 $30.00 $54.58 $54.21 $53.75 $20.00 $10.00 $- Ankeny Bondurant Adel Norwalk Waukee Adel Carlisle Indianola Adel Altoona Des Moines Panora Adel - Current Pleasant Hill Clive West Des Moines Johnston Grimes Windsor Heights Urbandale $53.40 $50.30 $49.60 $44.95 $44.20 $43.50 $41.65 $37.35 $37.28 $35.45 $34.12 $33.20 $31.80 $31.33 $28.80 $22.90 $21.65

7 Xenia Rural Water $ Panora Adel $64.70 $74.87 Adel Pleasant Hill Adel Waukee Johnston Grimes Adel Current Windsor Heights Bondurant Clive Altoona Norwalk Indianola $51.50 $47.70 $43.35 $41.70 $39.09 $37.77 $37.25 $36.95 $36.60 $35.50 $35.05 $33.20 $32.75 Urbandale $29.40 West Des Moines Carlisle Ankeny Des Moines $28.22 $27.50 $27.01 $26.55 $ $ $80.00 $60.00 $40.00 $20.00 $ Monthly Water Fees for 5000 gallon User