The river Lomena flows in Kaisiadorys district, the river Neris left tributary. Length of the river 30 km, the basin area 193 km ². The source at Kaisiadorys town. Flows to the north. Flows into the river Neris 57 km from its mouth at Tartokas village. Average gradient 211 cm/km. Average rated discharge at the mouth 1.18 m³/s.

At high water level. Spring flood, or after heavy rains.
Rapids, shalows, strainers.
WW 0/1 (2).

13.0 left Bistrinycia. left Lomeniai. From Kaisiadorys - Lomeniai road to the confluence 250 m. Average rated discharge approx. 0,6 m³/s.
12.8 Small bridge. right Svirplionys. left Lomeniai.
11.8 right Nota. The river meanders between hills through forest. In some places the banks steep. A lot of strainers. Average gradient to 7.1 km 166 cm/km. Average rated discharge approx. 1 m³/s. The river width 4-8 m. In the riverbed stones, in some places boulders.
8.9 right Nepreksta.
7.1 Average gradient to 4.4 km 163 cm/km.
5.8 left Verkstine.
4.4 Average gradient to the mouth 273 cm/km. The river wider, amount of strainers decreases. Stones, small rapids.
1.4 right the brook L-2. left hillfort Tartokas.
1.3 Small bridge. right Tartokas.
0.3 Jonava - Zasliai road bridge. Tartokas. Forest ends. Current calms.
0.0 The Lomena flows into the river Neris.