Failure frequency of water supply networks in the Podlaskie voivodeship

Abstract

This article describes the subject matter of the failure frequency of water supply pipes in Poland. The introduction to the article describes the causes of failures in the water supply network as well as a tool for assessment of the failure frequency of water supply pipes, i.e. damage intensity index. The status of Polish literature concerning the problem of failure frequency of water supply networks is also presented, and attention is paid to the absence of studies within the area of the Podlaskie voivodeship. The research part of the article presents the results of calculations of failure frequency indexes for water supply networks in the Podlaskie voivodeship. Materials from the Central Statistical Office for the period of 2015–2017 served as the basis for studies. Damage intensity indexes throughout the entire Podlaskie voivodeship were analyzed. The status of failure frequency of water supply networks was assessed in poviats of the Podlaskie voivodeship during the years 2015–2017. The mean level of failure frequency of water supply networks was also compared between the Podlaskie voivodeship, other voviodeships and the national average. As a result of calculations that were carried out, reference material was obtained for current and future studies concerning failure frequency of water supply networks in the Podlaskie voivodeship as well as other voivodeships of northern Poland.

Analysis of the Negative Daily Temperatures Influence on the Failure Rate of the Water Supply Network

“…In the next stage, the relationship between the material of the pipes that failed and daily temperature was investigated with the use of the failure rate λ M according to the Equation (4); the relationship between the cause of failure and daily temperature using the failure rate λ C according to the Equation (5) and the relationship between the diameter of failed pipes and daily temperature using the failure rate λ D according to Equation (6). (6) where: λ M(ti;ti+1> -the failure rate for pipes of a given material at a given daily temperature in range (ti;ti + 1>, λ C(ti;ti+1> -the failure rate resulting from a given cause at a given daily temperature in range (ti;ti + 1>, λ D(ti;ti+1> -the failure rate for pipes of a given diameter at a given daily temperature in range (ti;ti + 1>, n M(ti;ti+1> -number of failures of pipes made of a given material occurring at daily temperature in range (ti;ti + 1>, n C(ti;ti+1> -number of failures resulting from a given cause occurring at daily temperature in range (ti;ti + 1>, n D(ti;ti+1> -number of failures of pipes with a given diameter occurring at daily temperature in range (ti;ti + 1>, d (ti;ti+1> -number of days with daily temperature in range (ti;ti + 1>, L M -total pipe length for a given material, km. L N -average pipe length for a given type of network, km.…”

“…The reliability of the water supply system is understood as its ability to perform its functions, in accordance with the requirements in terms of its functioning and safety, i.e., providing consumers with water in the right amount, of appropriate quality, under the right pressure, at an acceptable price at any time [3][4][5]. Currently, the topic of water supply is faced with many problems related to, among the others, the lack of access to water in developing regions, the appearance of new pollutants in tap water (microplastics, pharmaceuticals) and the functioning of the existing and aging water supply systems [1,3,[5][6][7][8][9][10]. Problems related to the operation of existing water supply systems can be effectively solved by appropriate management, taking into account the minimization of water losses, improvement of the quality of the supplied water and increasing the reliability and safety of their operation [1,[5][6][7].…”

“…Currently, the topic of water supply is faced with many problems related to, among the others, the lack of access to water in developing regions, the appearance of new pollutants in tap water (microplastics, pharmaceuticals) and the functioning of the existing and aging water supply systems [1,3,[5][6][7][8][9][10]. Problems related to the operation of existing water supply systems can be effectively solved by appropriate management, taking into account the minimization of water losses, improvement of the quality of the supplied water and increasing the reliability and safety of their operation [1,[5][6][7]. In order to learn about the mechanisms responsible for the reliability and safety of the water supply system functioning, in recent years much research has been done.…”

“…In order to learn about the mechanisms responsible for the reliability and safety of the water supply system functioning, in recent years much research has been done. One of the directions of this research is the water supply network failure analysis [1][2][3][4][5][6][7][11][12][13][14][15]. Over the years, many factors that affect the failure rate of the water supply network have been identified [3,[5][6][7]11,[16][17][18][19].…”

“…One of the directions of this research is the water supply network failure analysis [1][2][3][4][5][6][7][11][12][13][14][15]. Over the years, many factors that affect the failure rate of the water supply network have been identified [3,[5][6][7]11,[16][17][18][19]. There can be distinguished internal (system) factors: pipe material, pipe diameters, age of the system, pressure in the water supply network, flow rate, quality of design, construction and operation of the system, and external (environmental) factors: climate (seasonality, climate change), weather conditions (temperature, rainfall, drought), soil and water conditions (type of soil, frost depth, groundwater level, corrosivity of the soil and groundwater).…”