Because two rivers- the Tigris and the Euphrates as well as some parts of the Nile- regularly flooded the region
You will want to consider the author's point of view in light of the fact that she may profit from the building project.
Look at the evidence within the question information. The author has 20 years of experience in construction and owns a local construction company. So if the city or town is considering a building initiative that will cost the town millions of dollars, the author of the editorial quite possibly hopes to bid for some of that construction work. It would be very good for her business.
Now, the fact that a construction company owner favors the building initiative doesn't mean her views should be rejected simply because of her position in the construction industry. If her views are valid and provide solid arguments in favor of the project, those views should be considered on their merits. At the same time, perspectives from other local citizens should be considered too, in terms of environmental impact of the project, costs and affordability, how the building initiative will benefit residents of the community, etc.
