A report by Turkish police on last year’s floods in northern Turkey, the deadliest in recent memory, pinpoints a string of factors, mainly haphazard, faulty development in residential areas that experienced deaths.

Dozens of people were killed in three provinces in the country’s Black Sea region in August when unprecedented floods inundated small towns. Bozkurt, a town in Kastamonu province, was hit hardest by the floods that claimed at least 65 lives, while eight others remain missing.

The Interior Ministry had launched an investigation following the floods and the newly formed Disaster Criminal Investigation Department of the police handled the probe. Officials from the department worked in the disaster zone for months and compiled a comprehensive report revealed on the website of the Sabah newspaper on Monday. The report lists a number of reasons for the great toll of the disaster and among them is the "narrowed" bed of Ezine Stream that flows through Bozkurt, leading it to overrun its banks. The "narrowing" was a human-made process, the report highlights while citing excessive precipitation as the main cause of the disaster.

The construction of residential buildings on the riverbed, the presence of a timber storage area near the same bed and faulty construction of bridges along the stream are among other factors listed in the report as culprits of the high death toll and damage.

Though the Black Sea region, especially its eastern parts, is known for its potential flood risk, Bozkurt was an exception. The precipitation usually recorded in one year hit the town over a span of only two days. Rainwater from the Küre mountains in the region further aggravated the situation when they ran into the Ezine stream. Water levels had reached 4 meters (13 feet) in some spots, carrying away everything, from pieces of buildings to people and vehicles, into the Black Sea.

The report says the Ezine stream covered a wider area and had an S-shape before the 2000s and it was narrowed over time and artificially confined to a flat course flowing into the Black Sea. It points out that multistory residential buildings were built in the same period in the areas reclaimed from the stream and those were the first places to be exposed to damage from the floods.

It also touches on the high number of timbers washed away by the floods, which obstructed the water flow in areas with bridges and inflicted damage on some buildings. It says the timbers aggravated the damage as the timber storage area was located in a place close to the stream.

Another factor that aggravated the situation was the bridges themselves, the report says. Instead of arched bridges, flat bridges were constructed across the stream in recent years, preventing the free flow of water and debris, and causing the stream to overflow its banks.

Floods are often worsened by the development of river beds, something unfortunately common in the Black Sea region where rough, uneven terrain leaves little space for the construction of new residential areas for locals. Yet, experts say this should be prevented to minimize the damage from future floods.

As for Bozkurt, the town was rocked recently by a new flood that devastated some bridges temporarily built for transportation after last year’s floods. Three bridges were shut down last week when the water levels sharply rose across the Ezine stream on May 6.