Bacău County is a county (județ) of Romania, in Western Moldavia, with its capital city at Bacău. It has one commune, Ghimeș-Făget, in Transylvania.
Onești is a city in Bacău County, Romania, with a population of 39,172 inhabitants. It is situated in the historical region of Moldavia.
The Suceava is a river located in the north-east of Romania and western Ukraine. It is a right tributary of the river Siret. It discharges into the Siret in the town Liteni, 21 km south-east of the city of Suceava.
The Trotuș is a river in eastern Romania, a right tributary of the river Siret. It emerges from the Ciuc Mountains in the Eastern Carpathians and joins the Siret in Domnești-Sat near Adjud after passing through Comănești and Onești in Bacău County. The total length of the Trotuș from its source to its confluence with the Siret is 162 km (101 mi). Its basin area is 4,456 km2 (1,720 sq mi).
The Bărzăuța is a right tributary of the river Uz in Romania. It discharges into the Uz near Valea Uzului. Its length is 26 km (16 mi) and its basin size is 156 km2 (60 sq mi).
The Tarcău is a right tributary of the river Bistrița in Romania. It discharges into the Bistrița in the village Tarcău. It flows through the villages Ardeluța, Schitu Tarcău, Brateș, Cazaci and Tarcău. Its length is 33 km (21 mi) and its basin size is 392 km2 (151 sq mi).
The Râul Negru is a left tributary of the river Olt in Romania. It discharges into the Olt in Lunca Câlnicului. It flows through the villages Lemnia, Lunga, Catalina, Hătuica, Surcea, Telechia, Bita, Reci, Sântionlunca, Ozun, Băcel, Chichiș and Lunca Câlnicului. Its length is 88 km (55 mi) and its basin size is 2,349 km2 (907 sq mi).
The Cașin is a right tributary of the river Râul Negru in Romania. It discharges into the Râul Negru in Catalina. It flows through the villages and towns Plăieșii de Sus, Plăieșii de Jos, Iacobeni, Valea Seacă, Sânzieni, Târgu Secuiesc and Catalina. Its length is 54 km (34 mi) and its basin size is 482 km2 (186 sq mi).
The Turia is a right tributary of the river Cașin in Romania. It flows into the Cașin in the city Târgu Secuiesc. Its length is 24 km (15 mi) and its basin size is 127 km2 (49 sq mi).
The Pârâul Primejdios is a right tributary of the river Cașin in Romania. It flows into the Cașin near Iacobeni. Its length is 14 km (8.7 mi) and its basin size is 80 km2 (31 sq mi).
The Tazlău is a left tributary of the river Trotuș in Romania. Its source is in the Tarcău Mountains. It discharges into the Trotuș in Slobozia, near the city Onești. The Belci Dam, which failed in 1991, was built on the river Tazlău. The following villages are situated along the river Tazlău, from source to mouth: Tazlău, Frumoasa, Balcani, Ludași, Pârjol, Tărâța, Hemieni, Scorțeni, Tescani, Berești-Tazlău, Sănduleni, Livezi, Helegiu and Slobozia. Its length is 12 km (7.5 mi) and its basin size is 38 km2 (15 sq mi).
The Haloșul Mare is a right tributary of the river Cașin in Romania. It flows into the Cașin near Mănăstirea Cașin. Its length is 8 km (5.0 mi) and its basin size is 20 km2 (7.7 sq mi).
The Buciumi is a right tributary of the river Cașin in Romania. It flows into the Cașin near Răcăuți. Its length is 11 km (6.8 mi) and its basin size is 18 km2 (6.9 sq mi).
The Cașin is a right tributary of the river Trotuș in Romania. It discharges into the Trotuș in Onești. Its length is 54 km (34 mi) and its basin size is 308 km2 (119 sq mi).
The Curița is a left tributary of the river Cașin in Romania. It discharges into the Cașin in the village Cașin. Its length is 17 km (11 mi) and its basin size is 31 km2 (12 sq mi).
The Caminca is a left tributary of the river Trotuș in Romania. It discharges into the Trotuș in Brusturoasa. Its length is 29 km (18 mi) and its basin size is 75 km2 (29 sq mi).
The Izvorul Alb is a left tributary of the river Asău in Romania. Its source is in the Tarcău Mountains. It discharges into the Asău in Păltiniș. Its length is 10 km (6.2 mi) and its basin size is 31 km2 (12 sq mi).
The Bârsănești is a right tributary of the river Tazlău in Romania. Its length is 13 km (8.1 mi) and its basin size is 23 km2 (8.9 sq mi).
The Brodina is a right tributary of the river Suceava in Romania. It discharges into the Suceava in the village Brodina. Its length is 29 km (18 mi) and its basin size is 142 km2 (55 sq mi).
The Bârnărel is a right tributary of the river Bistrița in Romania. It flows into the Bistrița in Crucea. Its length is 13 km (8.1 mi) and its basin size is 42 km2 (16 sq mi).
