Case Background: Starting from a Procurement Plan — In early 2025, the Urban Management Bureau of a district in Handan proposed procuring a batch of compact sewage treatment vehicles as part of its annual sanitation equipment upgrade plan. These vehicles are intended for routine cleaning and emergency handling of sewer lines and septic tanks in old urban residential communities. The budget was capped at approximately RMB 201,000 per unit, with requirements for maneuverability in narrow alleys and operability by drivers holding only a Class C1 driver’s license—meaning the vehicles must be registered under China’s blue license plate category. After multiple rounds of tender evaluation, five units of the CLW5070GSSD6 sewage treatment vehicle—built on the Dongfeng D6 chassis and equipped with Chengli’s proprietary superstructure (officially certified model)—were delivered. Since being put into service in April 2025, these vehicles have accumulated over 300 operational hours, covering more than 80 locations across seven subdistricts within the district. We interviewed Mr. Wang, one of the drivers responsible for daily operation, and below is his firsthand feedback. I. Real-World Driver Experience: From 'Afraid to Drive Large Vehicles' to 'Driving Like an SUV' Mr. Wang holds a Class B2 driver’s license and has three years of experience primarily operating water-sprinkling trucks. Initially, he had reservations about operating a blue-plate sewage treatment vehicle: 'I worried it would be too small to control properly and that its high center of gravity might compromise stability.' However, after actual operation, he remarked, 'This vehicle is far easier to drive than I imagined.' Visibility & Handling: The Dongfeng D6 cab features a car-like design, with slim A-pillars minimizing blind spots and wide-angle rearview mirrors. During reversing and turning maneuvers within residential neighborhoods, virtually no visual blind zones exist. The steering wheel is equipped with hydraulic power assist, delivering light and responsive steering—'one-handed steering requires minimal effort.' Powertrain & Chassis: Powered by a Tier VI diesel engine delivering a maximum output of approximately 85 kW, the vehicle provides ample low-end torque. Even when fully loaded (gross vehicle weight approx. 4.5 tons), it climbs 30-degree inclines effortlessly. Its chassis utilizes Dongfeng’s original factory frame; ride comfort is notable—even over speed bumps—with effective vibration damping. Noise & Comfort: Acoustic insulation in the cab keeps combined engine and vacuum pump noise levels around 70 dB during operation, enabling clear two-way radio communication. The air conditioning cools rapidly even in summer heat, and the seat offers multi-directional adjustment. Mr. Wang summarized: 'Driving this vehicle feels much like driving an SUV—except it’s slightly longer (approx. 5.9 meters). Yet its tight turning radius makes navigating narrow alleys and sharp right-angle turns effortless.' II. Operational Convenience: A 'Game-Changing Advantage' Enabled by Blue-Plate Classification & Class C1 Licensing The greatest advantage of blue-plate sewage treatment vehicles lies in their low driver qualification threshold. According to FAQ documentation in our knowledge base, the CLW5070GSSD6 model has a gross vehicle weight ≤ 4.5 tons and overall length < 6 meters—fully compliant with Class C1 driver’s license authorization. Mr. Wang noted: 'Several newly hired drivers in our team hold only Class C1 licenses; after just three days of training, they were confident enough to operate independently.' Control Panel: Chengli’s integrated sewage treatment system features an electronic control panel with eight clearly labeled buttons—each controlling functions such as the vacuum pump, discharge valve, and cleaning pump—accompanied by intuitive indicator lights. 'It’s plug-and-play operation—you grasp it instantly upon first glance.' Tank & Piping System: The tank capaci