Abstract: Gampong Kuta Ateuh is the center of settlement and government office areas concerned to guard its territory against flooding inundation, so it is necessary a representative drainage handling. The purpose of this research is to evaluate the performance of drainage network of Gampong Kuta Ateuh based on channel capacity on existing spatial condition, and to evaluate the performance of drainage network based on channel capacity on Sabang City Spatial Condition. Based on the result of performance evaluation of drainage network at Gampong Kuta Ateuh on existing spatial condition based on channel capacity obtained 2 (two) unsafe channel segment which yield minus value (-) for Qs-QT. Based on spatial arrangement that is at least the proportion of 30% RTH (Green Open Space) of each DTH produces 5 (five) unsecured channel segments, this shows current RTH Kota Sabang 30%. A value of the runoff coefficient (C) has a range between 0,5453 and 0,5025. Spatial arrangement of this research has resulted in many channels damaged by the arrangement of road landscapes that do not follow the Ministerial Decree No.05 / PRT / M / 2012 on Tree Planting Guidance on Road Network Systems. The path of plant on the road should be placed on the edge of traffic lane and pedestrian path, after the pedestrian path then the channel. Abstrak: Gampong Kuta Ateuh merupakan pusat permukiman dan kawasan perkantoran pemerintah yang berkepentingan untuk menjaga wilayahnya terhadap banjir genangan sehingga perlu penanganan drainase yang representatif. Tujuan dari penelitian ini adalah mengevaluasi kinerja jaringan drainase Gampong Kuta Ateuh berdasarkan kapasitas saluran terhadap kondisi tata ruang existing, dan mengevaluasi kinerja jaringan drainase berdasarkan kapasitas saluran terhadap kondisi Penataan Ruang Kota Sabang. Berdasarkan hasil evaluasi kinerja jaringan drainase Gampong Kuta Ateuh pada kondisi tata ruang existing berdasarkan kapasitas saluran diperoleh 2 (dua) ruas saluran yang tidak aman dimana menghasilkan nilai minus (-) untuk ...