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Research was conducted to estimate grass consumptive use and return flow (deep percolation) in urban lawn water use. Two types of small lysimeters were used - a drainage-type lysimeter of 40 cm diameter and 60 cm depth and a weighing-type lysimeter of 30 cm diameter and 60 cm depth. A large hydraulic weighing-type lysimeter of 1 [m.sup.2] surface area and 1.3 m depth was used as the reference for comparison. The amount of water application, deep percolation, and change in soil moisture content were measured for the 1992-1994 summer seasons, and evapotranspiration (ET) was calculated using a volume balance equation. The results suggest that the small lysimeters are of acceptable accuracy compared to large lysimeters for estimating evapotranspiration. The weighing-type small lysimeters appeared to be more consistent but underestimated evapotranspiration compared to the drainage-type lysimeters. The results for estimating deep percolation with the small lysimeters are not conclusive yet.