Know Your Zone
The Nevada County Sanitation District services 11 zones throughout the County and each zone is different from the next. Learn more about the specifics of your sewer zone.
Zone 1 - Lake Wildwood, Penn Valley, and Valley Oak Court (Consolidated)
In 2021, the three zones (Lake Wildwood, Penn Valley, and Valley Oak Court) were consolidated as part of the 2021 Rate Study to help consolidate and reduce overall capital expenses for the plant.
Annual Service Fees
Annual Service Fee rates can be found on NCSD Rates Page. Rates reflect the current Fiscal year through the Fiscal Year 2025/26
Zone 1 Maps
Treatment Plant
The Lake Wildwood Treatment Plant was established on June 23, 1970, and is located at 12622 Pleasant Valley Road, Penn Valley CA 95946.
The Lake Wildwood Treatment Plant services approximately 3,266 Connected EDUs (Equivalent Dwelling Units) and 756 Standby EDUs for a total of nearly 4,022 EDUs.
Interested in taking a tour of the Lake Wildwood Treatment Plant? Check out our link on how to register for or set up a tour
Equipment
- Headworks
- 2 – Oxidation Ditches
- 2 – Clarifiers
- Testing Lab
- RAS Pumping Facilities
- Aerated Sludge storage pond
- Walker tank
- Centrifuge
- Pressure filters
- Ultra Violet Disinfection
- Equalization Basin
- Grit Remover
- Odor Control
Lake Wildwood – Zone 1
EDUs
- 2912 Connected EDUs
- 648 Standby EDUs
- 3567 Total Allocated EDUs
Collection System
Gravity Sewer Collection System (line cleaning/lift station maintenance/Manhole Evaluations/Service Calls)
- 41 Miles of 6- to 12-inch gravity sewer collection main
- 2 miles of 4- 8-inch sewer force main
- 559 Manholes
- 51 cleanouts
- 14 sewer pump stations (21-34)
- 28 pumps (2hp-88hp)
- 10 permanent standby generators
- 2 portable standby generators
Penn Valley – Zone 6 – Est. 1988
EDUs
- 348 Connected EDUs
- 108 Standby EDUs
- 456 Total Allocated EDUs
Collection System
Septic Tank Effluent Pump (STEP) System (Service calls/PVMHP Pump and Tank maintenance/RV APTS – Pump and Tank Maintenance-Taco Bell/Shell Station 2 x per year maintenance both tanks/ARV maintenance/Tack Room 1 x per year maintenance or as needed/lift station maintenance)
- 348 STEP systems
- 17 Miles of 2- to 6-inch pressure collection force main
- 1 sewage pump station
- 1 standby generator
Valley Oak Court – Zone 12 – Est. 2005
EDUs
- 6 Connected EDUs
Collection System
Septic Tank Effluent Pump (STEP) System (service calls/pump & tank maintenance/pump tanks every 5 years or as needed)
- 1/8 mile of pressure sewer line
- 6 STEP systems
- Pump to the community leach field
FAQs and Zone-Specific Information
Please see the Frequently Asked Question on Lake Wildwood.
Zone 2 - Lake of the Pines, Darkhorse Est. 6/13/72 and Higgins Village- Est. 2003
(Consolidated)
In 2021, the two zones (Lake of the Pines and Darkhorse) were consolidated as part of the 2021 Rate Study to help consolidate and reduce overall capital expenses for the plant. Higgins Village, established in 2003 , had been consolidated into this zone upon its establishment in 2003.
Annual Service Fees
Annual Service Fee rates can be found on NCSD Rates Page. Rates reflect the current Fiscal year through the Fiscal Year 2025/26.
Zone 2 Maps (Consolidated)
Treatment Plant
The Lake of the Pines Wastewater Treatment Plant was established on June 13, 1972, and is located at 10984 Riata Way Auburn CA 95602. The Lake of the Pines Treatment Plant services approximately 2,331 connected EDUs (equivalent dwelling units) and 155 standby EDUs for a total 2,486 allocated EDUs.
Equipment
- 4 ponds
- Testing lab
- Headworks
- Membrane Bio Reactor
- Blowers
- Centrifuge
- Chlorine Contact Basins
Lake of the Pines and Darkhorse - Zones 2 & 10
EDUs
- 2,331 connected EDUs
- 155 standby EDUs
- 2,486 total allocated EDUs
Collection System
The Collection system is a Gravity Sewer Collection System (line cleaning/lift station maintenance/Manhole Evaluations/Service Calls/E-one pump system maintained by customer in Darkhorse)
- 26 miles of 6- to 15-inch gravity sewer collection main
- 8 miles of 4- to 10-inch pressure sewer force main
- 12 sewer pump stations (1-11) (12 in Darkhorse)
- 25 pumps (2hp-20hp) (Lift Station 1 has three 19 hp pumps)
- 386 manholes
- 68 cleanouts
- 8 permanent standby generators
- 2 portable standby generators
Higgins Village - Zone - 11
EDUs
- 47.8 connected EDUs
Collection System
Septic Tank Effluent Pump (STEP) System (Check and monitor septic tanks and pumps/ replace as needed/measure sludge levels and notify the owner if they need to have solids removed)
- 1 mile 2-inch pressure sewer line
- 5 effluent pump tank systems
- 10 pumps
- Effluent tanks pumped by NCSD
- Grease and solids hauled by contract hauler by owners
Zone 4 North San Juan
The North San Juan zone was established on April 10, 1980
Annual Service Fees
Annual Service Fee rates can be found on NCSD Rates Page. Rates reflect the current Fiscal year through the Fiscal Year 2025/26
Zone 4 Map
Treatment Plant
Equipment
- 2 septic tanks
- Community leach field
EDUs
- 86 connected EDUs (equivalent dwelling units)
- 0 standby EDUs
Collection System
- Gravity sewer collection system (Yearly line cleaning/lift station maintenance/manhole evaluation and repair/service calls)
- 2 miles of 6-inch gravity collection main
- 0.5 miles of 4-inch pressure sewer force main
- 35 manholes
- 14 cleanouts
- 1 sewer pump station (41)
- 2 pumps (10hp)
- 1 standby generator
Zone 5 - Gold Creek
The Gold Creek Zone was established in 1983.
Annual Service Fees
Annual Service Fee rates can be found on NCSD Rates Page. Rates reflect the current Fiscal year through the Fiscal Year 2025/26.
Zone 5 Map
Treatment Plant
Equipment
- 2 community septic tanks
- Community leach fields
EDU's
- 44 connected EDUs (equivalent dwelling units)
Collection System
- Gravity sewer collection system (yearly line cleaning/manhole evaluation and repair/service calls)
- 0.3 miles of 6" gravity sewer collection main
- 9 manholes
- 5 cleanouts
Zone 7- Mountain Lake Estates
Established 1989
Annual Service Fees
Annual Service Fee rates can be found on NCSD Rates Page. Rates reflect the current Fiscal year through the Fiscal Year 2025/26.
Zone 7 Map
Treatment Plant
Equipment
- Community septic tank
- Community leach field
EDUs
- 40 connected EDUs (equivalent dwelling units)
- 6 standby EDUs
- 46 total allocated EDUs
Collections System
- Septic tank effluent pump (STEP) system (service calls/pump and tank maintenance/pump tanks every 5 years or as needed)
- 47 step systems
- 2 miles 2- to 4-inch pressure collection main
Zone 8 - Cascade Shores
The Cascade Shores zone was established 1990.
Annual Service Fees
Annual Service Fee rates can be found on NCSD Rates Page. Rates reflect the current Fiscal year through the Fiscal Year 2025/26.
Zone 8 Map
Treatment Plant
Equipment
- EQ Tank
- Headworks
- Mixed Membrane Bio Reactor
- UV
- Clarifier
- Filters
Collection System
- Gravity Sewer Collection System (Yearly tank & pump maintenance at LS 61/yearly line cleaning/Pump Digester at the CSWWTP as needed)
- 2 Miles 4”-6” gravity sewer collection main
- 16 Manholes
- 4 cleanouts
- 0.7 miles of 2” sewer pressure main
- 1 sewer pump station (61)
- 3 pumps (1.5hp)
EDU's
- 89 Connected EDUs
- 19 Standby EDUs
- 108 Total Allocated EDUs
Zone 9 - Eden Ranch
Annual Service Fees
Annual Service Fee rates can be found on NCSD Rates Page. Rates reflect the current Fiscal year through the Fiscal Year 2025/26.
Zone 9 Map
Treatment Plant
- The treatment plant consists of 2 septic tanks, effluent pumps, and a community leach field.
Collection System
- Gravity sewer collection system (Yearly line cleaning/lift station maintenance/manhole evaluation and repair/service calls)
- 2 miles of 6-inch gravity collection main
- 0.5 miles of 4-inch pressure sewer force main
- 35 manholes
- 14 cleanouts
- 1 sewer pump station (41)
- 2 pumps (10hp)
- 1 standby generator
EDUs
- 86 connected EDUs (equivalent dwelling units)
- 0 standby EDUs