coşkulu derelerin aktığı 

ne demek?

yardim edecegine cok tesekkur edrim

Your sentence is missing context , but so far it means;

coşkulu derelerin aktığı ……?

……………………….wherein the  wild [fast and destructive] water streams are flowing …..

if  the sentence was ;

coşkulu derelerin aktığı  vadi ----> The valley wherein the wild water streams are flowing ….

ty