[Objective] The use of a consumer unmanned aerial vehicle (UAV) was developed and evaluated to construct an engineering pile terrain model

that can provide data reference for urban soil and water conservation monitoring.[Methods] The consumer-level UAV DJI Elf 4Pro was used to perform vertical down photography and oblique photography of the land shape of a park under construction

and quickly construct a terrain model with different number of control points. Analysis of the relative accuracy was based on absolute accuracy

and a comparison of area and volume with approximate real values of two different aerial photography methods at different number of control points.[Results] ① The landform of the engineering pile with little terrain fluctuation was not suitable for 45° tilting aerial photography

it could increase the tilt angle to 70°; ② The overall accuracy of the vertical lower view aerial photography was better than that of the oblique cross aerial photography. The relative accuracy could reach the sub-meter level without the control point

and the earthwork measurement error was less than 5%; ③ Tilting aerial photography could improve elevation accuracy and earthwork measurement accuracy at rare control points

and the earthwork measurement error was less than 1% at five control points.[Conclusion] The construction of the engineering pile terrain model by the consumer UAV can achieve high precision with no control and rare control points. Quick

accurate

and 3D intuitive reflection of area and earthwork changes

it provides real-time and reliable data reference and decision-making basis for soil and water conservation program implementation and monitoring.