Penelitian ini bertujuan untuk mengetahui pengaruh limpasan air drainase terhadap kerusakan jalan. Penelitian ini menggunakan data primer berupa lebar dan panjang jalan, kerusakan jalan (jenis, tingkat, dan dimensi kerusakan), serta dimensi dan kondisi saluran, sedangkan data sekunder berupa data curah hujan 10 tahun terakhir dari GPM (Global Precipitation Measurement). Data kondisi perkerasan dianalisis menggunakan Metode Surface Distress Index (SDI) untuk mendapatkan nilai rating SDI. Data kondisi saluran dan curah hujan dianalisis untuk mendapatkan nilai Q eksisting dan Q rencana saluran drainase di setiap unit segmen. Nilai pengaruh drainase terhadap kerusakan jalan diperoleh dari analisis korelasi. Berdasarkan hasil penelitian yang dilakukan, pada segmen 4 diperoleh debit rencana saluran (Qr) = 4,330 m³/det, sedangkan dari hasil survei lapangan didapat kapasitas saluran (Qs) = 1,830 m³/det. Limpasan air memiliki hubungan kuat terhadap kerusakan Jalan To’lemo, di mana diperoleh nilai SDI = 160 sehingga kondisi jalan termasuk kategori rusak berat, yang memerlukan penanganan segera melalui perbaikan drainase dan perkerasan jalan agar kerusakan tidak semakin meluas. This study aims to determine the effect of drainage water runoff on road damage. This study uses primary data in the form of road width and length, road damage (type, level, and dimensions of damage), as well as channel dimensions and conditions, while secondary data in the form of rainfall data for the last 10 years from Global Precipitation Measurement. Pavement condition data is analyzed using the Surface Distress Index (SDI) Method to obtain the SDI rating value. Channel condition and rainfall data are analyzed to obtain the existing Q value and the planned Q value of the drainage channel in each segment unit. The value of the influence of drainage on road damage is obtained from correlation analysis. Based on the results of the study, in segment 4, the planned channel discharge (Qr) is obtained = 4,330 m³/sec, while the results of the field survey obtained channel capacity (Qs) = 1,830 m³/sec. Water runoff has a strong relationship to the damage to To'lemo Road, where the SDI value is obtained = 160 so that the road condition is categorized as severely damaged, which requires immediate treatment through drainage and road pavement repairs to prevent further damage.