Such reach covers 30 kilometers in length through flat terrain with zigzag watercourse/riverway(2选1).
1.河段,还可表示为channel segment,stream segment
2.题外：既先“河段”,后言“江道”,疑笔误（河道!）
“该河段长约30km,地势平坦,江道曲折”翻译成英语,不要翻译成Chinglish,要地道的英语.谢啦.
Such reach covers 30 kilometers in length through flat terrain with zigzag watercourse/riverway(2选1).
1.河段,还可表示为channel segment,stream segment
2.题外：既先“河段”,后言“江道”,疑笔误（河道!）