12/29/2023
1 RiversideCA.gov
Septic Receiving Station Receipt of
Domestic and Commercial Septic
Waste and Tipping Fees
Public Works Department
Mobility & Infrastructure Committee
January 11, 2024
RiversideCA.gov
2 BACKGROUND
• City of Riverside, Public Works Department, Wastewater Division is responsible for the collection, conveyance, and treatment of wastewater for over 93,000 customers within City limits. The Regional Water Quality Control Plant (RWQCP) treats an average of 27 MG day.
• RWQCP operates and maintains a septic receiving station which receives an average of 1.06 MG a month or 35,000 gallons per day. This station is a regional facility, accepting domestic septic waste with no service area restrictions. • Environmental Compliance staff identified instances of liquid waste haulers bringing commercial septic waste to RWQCP in violation of 14.12.205.
• Staff met with the Regional Water Quality Control Board (Region 8) discussed receiving non‐industrial and non‐ automotive commercial waste.
1 2
12/29/2023
2 RiversideCA.gov
3 ACCEPTANCE OF COMMERCIAL WASTE
• Commercial septic waste accounts for 15% of the total septic waste received. • Commercial septic waste is different from domestic septic waste in that commercial waste is typically stored in an underground holding tank (no leach lines) and includes an upstream control device, such as a clarifier and/or grease interceptor .
• Commercial septic waste has a higher potential of introducing pollutants that may upset the wastewater treatment system. RWQCP will implement safeguards in the liquid waste hauler permit to limit these exposures. • As of December 2023, one liquid waste hauler has entered a Compliance Order with the City and a second hauler is in discussion to enter into one. These Compliance Orders will be rescinded upon adoption by City Council. • Upon approval, the City of Riverside will operate the only wastewater treatment plant in the region accepting non‐ industrial and non‐automotive commercial septic waste.
RiversideCA.gov
4 WASTE TYPE AND LOAD ORIGINATION
Waste Type Received
Septage Waste (85%) Commercial Waste (15%)
Load Origination ‐ Commercial Waste
Commercial Waste: City (0.4%) Commercial Waste: non‐City (99.6%) Load Origination ‐ Septage Waste
Septage Waste: City (13.5%) Septage Waste: non‐City (86.5%) RWQCP –A Regional Facility
14% of all septic waste originated within the City
86% of all septic waste originated outside City limits
3 4
12/29/2023
3 RiversideCA.gov
5 CAPITAL IMPROVEMENTS & STAFFING
• Current operations include 1 septic receiving station and associated monitoring devices ‐ pH and Specific
Conductance.
• Project includes the installation of a second septic
receiving station, associated monitoring devices,
card swipe system and attendant structure.
• Two additional staff members will be needed to
operate the receiving station. These staff members
will cover the 7 day a week operation and duties will
include things such as logging deliveries, unloading
trucks, receiving & documenting manifests, taking
samples and verify each sample is in compliance
with permit regulations.
RiversideCA.gov
6 TIPPING FEE STUDY
• To accommodate the change to start receiving commercial septic waste, RWQCP retained Carollo Engineers to analyze the septic receiving station influent loading characteristics and tipping fees. • Carollo issued a technical memorandum, dated October 2023, entitled “Septic and Commercial Waste Tipping Fees.” • The completed study calculated tipping fees by determining the City’s unit cost to treat septic waste –f l o w , BOD and TSS, capital improvements, operations & maintenance and staffing. • The current septic waste tipping fee of $ 30.00 per 1000 gallons is over 18 years old and was established June 2005 by Resolution 20976.
• Septic and Commercial waste Tipping Fee’s are not subject Proposition 218 5 6
12/29/2023
4 RiversideCA.gov
7 STUDY RECOMMENDATIONS
Proposed Tipping Fee’s
$/1000 gallons
RiversideCA.gov
8 SEPTIC RECEIVING BENCHMARKING
7 8
12/29/2023
5 RiversideCA.gov
9 RECOMMENDATIONS
1. Recommend that the City Council adopt an Ordinance to amend the Riverside Municipal Code Title 14, Public Utilities, and Discharge of Wastes into the Public Sewer and Pollutants into the Storm Drain Systems, Section
14.12.120 Definitions, to include definitions for Commercial Septic Waste and Commercial Wastewater; and,
2. Recommend that the City Council adopt an Ordinance to amend the Riverside Municipal Code Title 14, Public Utilities, and Discharge of Wastes into Public Sewer and Pollutants into the Storm Drain Systems, Section
14.12.295 (M) Liquid Waste Haulers, to include Commercial Septic Waste; and,
3. Recommend that the City Council adopt a Resolution to amend the septic receiving station tipping fees and amend Resolution 20976.
9