Procurement Case of CN6 Dongfeng 3308 mm Wheelbase Sewage Treatment Vehicle by a Municipal Sanitation Department in Cangzhou: Case Analysis and Cost Breakdown. In municipal vehicle procurement, sewage treatment vehicles—due to their technical complexity and long-term operational costs—are often challenging for government buyers. This article analyzes a real-world procurement case involving a CN6 Dongfeng 3308 mm wheelbase sewage treatment vehicle acquired by a municipal sanitation department in Cangzhou. It examines the procurement plan and cost structure from perspectives including service life, major repair expenses, and depreciation characteristics—offering practical reference for similar organizations. I. Procurement Background and Requirements Analysis The municipal sanitation department in Cangzhou (hereinafter referred to as the 'Purchaser') launched its sewage treatment vehicle procurement project at the end of 2025, primarily for emergency response and routine cleaning of urban sewage pipelines and septic tanks. Key requirements were clearly defined: the vehicle must comply with China VI emission standards; feature a Dongfeng chassis with a 3308 mm wheelbase; possess complete official vehicle type approval documentation enabling normal registration and operation. The Purchaser’s budget was capped at approximately RMB 311,000 per unit, with plans to procure two units to cover sewage treatment tasks across its jurisdiction. Based on local procurement practices, such vehicles must meet the following core specifications: tank capacity ≥ 4 m³; high-vacuum suction pump (suction depth ≥ 7 meters); solid-liquid separation capability; and remote operation support. After multiple rounds of market research and competitive bidding, the Purchaser selected the solution offered by Chengli Special Purpose Vehicle Co., Ltd. (hereinafter 'Chengli'). With over 500 municipal sanitation clients nationwide—and prior deliveries of similar models, such as four high-pressure cleaning/suction trucks supplied to Sichuan municipal authorities—Chengli’s brand reputation and after-sales service capability proved decisive in winning the bid. II. Winning Proposal Analysis: Total Cost of Ownership (TCO) Over 5-, 8-, and 10-Year Periods In government procurement, purchase price alone is not the sole criterion; rather, Total Cost of Ownership (TCO) serves as the key metric for long-term decision-making. Below is a TCO analysis of Chengli’s CN6 Dongfeng 3308 mm wheelbase sewage treatment vehicle solution, based on publicly available tender information. The vehicle features a Dongfeng chassis with a 3308 mm wheelbase and an upper-body assembly designed independently by Chengli, with a tank capacity of approximately 4.5 m³, equipped with a vacuum pump and solid-liquid separation system. Referencing official parameters for Chengli’s CLW5070GSSD6 model, the vehicle’s gross vehicle weight is approximately 7 tons, with a rated payload of about 3 tons. According to feedback from the Purchaser, the unit price is approximately RMB 260,000 (per publicly disclosed tender data). Comparative Operating Cost Analysis for CN6 Dongfeng 3308 mm Wheelbase Sewage Treatment Vehicle (Unit: RMB 10,000) Cost Item | 5-Year Period | 8-Year Period | 10-Year Period Purchase Cost (incl. tax) | 26.0 | 26.0 | 26.0 Annual Operating Cost (fuel + maintenance + insurance) | ~3.5/year | ~3.8/year | ~4.2/year Cumulative Operating Cost | 17.5 | 30.4 | 42.0 Major Repair Costs (mid-life + end-of-life) | ~0 | ~2.5 | ~5.0 Estimated Residual Value | ~6.5 | ~3.5 | ~1.5 Total Cost of Ownership (TCO) | 37.0 | 55.4 | 71.5 Note: Operating costs are estimated based on local diesel prices, annual mileage (~17,000 km), and standard maintenance frequency; major repair costs reflect industry experience.