This research was conducted to evaluate water saving, yield performance and water productivity of onion and pepper by using Wetting Front Detector (WFD) under irrigated conservation agriculture in Dangeshita watershed experimental plots in Dangla, woreda during 2018/2019 irrigation season. The data collected included irrigation water applied, moisture content, plant height and yields. This was done from four water management groups that were irrigation with guidance of Wetting Front Detector with climate based irrigation scheduling (WFD-FAO), WFD with farmer‟s irrigation practice (WFD-FIP), crop water requirement (CWR) and farmer irrigation practice (FIP). WFD-FAO and WFD-FIP treatments were found to be good for irrigation water management. The overall findings of these experiments were that WFD-FAO irrigation water management system can save water (32.6 % for onion field, 22.3 % for pepper field) and increased yield (29 % for onion, 50 % for pepper) as compared with farmer irrigation practice. Similarly, WFD-FIP treatment irrigation water management system can save water (27.8 % for onion field, 32.4 % for pepper field) and increased yield (32 % for onion, 39.3 % for pepper) with respect to farmer irrigation practice. Water used by WFD-FAO and WFD-FIP treatments in onion field were however reduced by 15.26 % and 8.5 % respectively and yield were also decreased by 15.6 % and 12 % as compared to CWR treatment respectively. However, when WFD combined with farmers‟ practices, it performed very well. WFD-FAO and WFD-FIP treatments water productivity increased by 51 % and 50 % for onion production season and 60 % and 58 % for pepper production season compared to FIP treatment respectively. Although many indicators confirm that WFD-FAO and CWR treatments practicality at farmer‟s level is questioning as it is more computers based. Thus, the use of WFD-FIP treatment appears to be an alternative for water saving without negligible trade-off in yield.