Mitryasova, O. CHRONICLES OF THIRST: DOCUMENTING MYKOLAIV'S WATER SECURITY CHALLENGES AND SOLUTIONS IN A WAR-AFFECTED CITY: Monograph. Mykolaiv: PMBSNU, 2026, 124 p.

CHRONICLES OF THIRST: DOCUMENTING MYKOLAIV'S WATER SECURITY CHALLENGES AND SOLUTIONS IN A WAR-AFFECTED CITY 2.3. HYDROCHEMICAL PORTRAIT OF THE URBAN WATER NETWORK When we talk about the "Hydrochemical Chronicle of War", we often imagine the shores of the estuary. However, the most dramatic part of this story unfolds every day in every apartment where the resident turns on the tap. In the period from 2023 to 2024, a group of researchers from the Petro Mohyla Black Sea National University conducted a detailed "scan" of water flowing through the "arteries" of Mykolaiv using the high- precision photometric system eXact Strip Micro 20 (Fig. 2.6). This study covered all districts of the city: Zavodskyi, Central, Korabelny and Ingulsky. Chemical "stability" in question In the large puzzle of hydrochemical monitoring of Mykolaiv, the hydrogen index (pH) and total alkalinity take the place of fundamental constants. These are not just numbers in laboratory journals, but basic characteristics that determine the nature of the water. During the study period, these indicators became silent witnesses of a profound transformation of the city's water system. According to the results of measurements, the pH indicator in Mykolaiv taps steadily fluctuated between 7.6–8.1. At first glance, for the average consumer, these data may seem quite acceptable, because they confidently fit into the established state sanitary standards (6.5–8.5). However, scientific analysis reveals alarming trends behind this external stability. The shift of the hydrogen index towards a slightly alkaline environment is a direct indicator of high mineralization. Water in Mykolaiv is no longer just a liquid; It turned into a complex chemical solution oversaturated with salts. The pH values indicated that the water buffer systems were working at the limit of their capabilities, trying to stabilize the cocktail of chlorides and sulfates that got into the network after the forced transition to the intake from the estuary. Alkalinity as a technical and domestic challenge If pH is the "pulse" of water, then the total alkalinity is its "capacity", the ability to resist changes in acidity. The study recorded that in all districts of the city — from Korabelny to Central — alkalinity reached 5.6–6.0 mmol/dm³. For comparison: this value significantly exceeds the parameters of the "soft" Dnipro water, for which the city infrastructure has been preparing for decades. High alkalinity directly affects the daily life of every Mykolaiv resident. It radically changes the way water interacts with organic matter, in particular detergents. Residents of the city noticed: the usual soap or shampoo in such water almost does not foam, and 80