Post on 03-Jun-2020
© 2016 HDR, Inc., all rights reserved.
Northern California Pipe Users Group Sharing Technologies Seminar – February 21, 2019
Big Changes for a Small Town: The Freeport Septic Conversion Project
Kevin Calderwood Senior Project Manager HDR Folsom, CA
Linda Peters, PE
Associate Civil Engineer Sacramento Area Sewer District Sacramento, CA
Presenters
Provides wastewater collection services to 1.2 million customers in: o Unincorporated Sacramento County o Citrus Heights, Rancho Cordova, Elk Grove o Portions of Folsom and Sacramento
More than 300 wastewater professionals. 105 lift stations; over 4,600 miles of pipeline Conveys wastewater to the Regional San
interceptor system for treatment at the Sacramento Regional Wastewater Treatment Plant near Elk Grove
Sacramento Area Sewer District
Freeport, CA Project Location
13 candidate communities throughout Sacramento County o Many are decades old, do not meet current County and State regulatory requirements o May pose a contamination risk to groundwater and nearby drinking water wells
SWRCB Prop. 1 grant funding available to help communities fund these conversion projects
SASD Septic Conversion Program
Sacramento River community at the western edge of Sacramento County
Established in 1860 2010 Census population of 38 41 parcels, 29 occupied
Freeport, California
Large proportion of retired residents Rely on wells for drinking water and septic
systems for wastewater disposal Many septic systems are decades old River-side lots are small, with inadequate
separation between septic systems and wells
Excellent candidate for septic conversion project
Freeport, California
Five alternatives were identified o Alternative 1 – “Do Nothing” o Alternative 2 – Gravity system o Alternative 3 – Low-Pressure Grinder Pump
System o Alternative 4 – Gravity + Lift Station and Force
Main System o Alternative 5 – “Hybrid” System
Project Design Alternative Evaluation
Alternative 1 – “Do Nothing” o Does not meet project objectives
of eliminating septic systems and protecting water quality
o Eliminated from further consideration
Project Design Alternative Evaluation
Alternative 2 – Gravity System o Infeasible due to length of sewer
required and insufficient depth of available connection point to existing sewer system
o Eliminated from further consideration
Project Design Alternative Evaluation
Alternative 3 – Low-Pressure Grinder Pump System o Determined to be feasible –
included in detailed evaluation o Lower capital costs o O&M costs higher for property
owners, offset partly by elimination of septic maintenance costs
o Lower easement acquisition costs o Simpler permitting
Project Design Alternative Evaluation
Alternative 4 – Gravity Sewer + Lift Station and Force Main System o Determined to be feasible –
included in detailed evaluation o Higher capital and long-term O&M
costs o Higher easement acquisition costs o More challenging permitting
Project Design Alternative Evaluation
Alternative 5 – “Hybrid” System o Determined to be feasible –
included in detailed evaluation o Combination of low-pressure grinder
pump and gravity + lift station systems
o Highest capital costs o Long term operation and
maintenance costs for both District and property owners
o High property acquisition costs o Challenging permitting o “Worst of both worlds” alternative
Project Design Alternative Evaluation
Alternative 3 – Low-Pressure Grinder Pump System identified as preferred alternative
Project Design Alternative Evaluation
Single pump 70 gallon capacity
Up to 700 gpd
Single pump 150 gallon capacity
Up to 1,500 gpd
Dual pump 150 gallon capacity
Up to 3,000 gpd
Quad pump 486 gallon capacity
Up to 7,000 gpd
E-one Low-Pressure Grinder Pump Systems
Grinder pump at each property with a functioning septic tank
1-1/4” pressure laterals Common 2” to 3” force main in
Freeport Blvd. HDD through existing Regional San
easement north of Cosumnes River Blvd.
SASD discharge manhole 8” gravity sewer segment connecting
to existing City of Sacramento manhole
Project Components
Each property requires “back-yard” work o Abandonment of existing septic tank o Installation of grinder pump o Rerouting existing house lateral o Installation of pressure lateral o Sufficient electrical supply
Design Challenges Working on Private Property
Design Challenges Working on Private Property Drawing set contains specific drawings for each
property
o Property owner at northern portion of the project unwilling to grant easement
o Pipeline will be installed within existing Regional San’s easement for their Sacramento Forcemain
o Easement requirements dictate construction methods: • Minimum 6-feet of cover • HDD construction (no open-cut)
Design Challenges Working in Existing Easements
Connection to existing City of Sacramento manhole
Narrow, curved alignment of easement requires open-cut
Design Challenges Working in Existing Easements
o Mature trees • Tree survey completed during design • Protection requirements included in contract
documents o Potential protected species
• Swainson’s Hawk • Burrowing Owl
o Potential cultural/tribal resources o Tree survey completed during design o IS/MND and MMRP prepared by Sacramento
County Planning and Environmental Review
Design Challenges Environmental Issues
Caltrans Encroachment Permit o Freeport Blvd is State Highway 160
Central Valley Flood Control Board o Work in the vicinity of Sacramento River levees
Sacramento County Encroachment Permit o For traffic control needed on Cosumnes River Blvd.
Project Permitting
o Public Meetings • Determine public interest • Review design and demo pump • Upcoming meeting to finalize participation
o Outreach to residents • Postcards and project newsletters • Door-to-door
Public Outreach
Prop 1 Grant Funding: State Water Resources Control Board Small Communities Wastewater Grant Confluence Regional Partnership Program Sacramento County Economic Development Fee Credits Other discretionary funds
Project Funding
Combined funding is expected to make the project cost-free to residential customers
© 2016 HDR, Inc., all rights reserved.
Northern California Pipe Users Group Sharing Technologies Seminar – February 21, 2019
Big Changes for a Small Town: The Freeport Septic Conversion Project
Questions?