AU2009200516B2

AU2009200516B2 - System for distributing water with diagnosing leakage of water

Info

Publication number: AU2009200516B2
Application number: AU2009200516A
Authority: AU
Inventors: Takeshi Inoue; Futoshi Kurokawa; Toshihiro Murashita; Naoto Oishi; Yoshiyuki Sakamoto; Katsuya Yokokawa; Atsushi Yukawa
Original assignee: Toshiba Corp; City Of Kitakyushu
Current assignee: Toshiba Corp; City Of Kitakyushu
Priority date: 2008-02-13
Filing date: 2009-02-10
Publication date: 2011-02-10
Anticipated expiration: 2029-02-10
Also published as: AU2009200516A1

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Standard Patent Applicant (s): KABUSHIKI KAISHA TOSHIBA and City of Kitakyushu Invention Title: System for distributing water with diagnosing leakage of water The following statement is a full description of this invention, including the best method for performing it known to me/us: P80219.AU PatSet_FWing Appcation 2009-2.10.doc (M) - 1A TITLE OF THE INVENTION SYSTEM FOR DISTRIBUTING WATER WITH DIAGNOSING LEAKAGE OF WATER BACKGROUND OF THE INVENTION 5 The present invention relates to a water distribution management system of waterworks facility, and particularly to a technique for water leakage diagnosis for water distribution network. A quite large percentage of the waterworks 10 facility is occupied by the water distribution facility for distributing pure water to consumers. The durability life of a water distributing pipe is estimated to be about 40 to 45 years and usually, the water distributing pipes are replaced with new ones to 15 meet a renewal period in viewpoints of the years in which they are buried. As for the renewal of pipes, attentions have been paid to effective renewal of the pipes in order to improve so-called rate of effectiveness (or 20 effective recovery rate) as well as to renew old pipes in terms of the years in which they are buried. The rate of effectiveness mentioned here means a percentage of the amount of water (effective water amount) consumed effectively to the total distributed 25 amount from a water distribution reservoir. That is, the rate of effectiveness is the amount of effective water, divided by total distributed amount of water.

-2 Further, the effective recovery rate means a percentage of the amount of water (amount of water which undergoes the effective recovery) which provides revenue in the form of water charge with respect to the effective 5 amount of water. That is, the effective recovery rate is the amount of water which undergoes the effective recovery, divided by total distributed amount of water. To improve the rate of effectiveness (effective 10 recovery rate), it is indispensable to take measures for preventing a water leakage from a distribution pipe and as this measure, information about distribution of water for diagnosing a water leakage is important. Improvement of the rate of effectiveness due to 15 prevention of water leakage not only reduces a load on the water circulation system but also provides an effect of reducing cost on stages of purifying water and distributing water. As a prior art relating to monitoring and 20 detection of water leakage, there is a proposal regarding a water work meter lid with water leakage monitoring function and a water work meter (for example, see Japanese Patent Application Laid-Open (JP A) No. 2004-191139). Additionally, there is also a 25 proposal about a water leakage detection system which executes both checking with a water work meter and water leakage inspection at the same time (for example, -3 see JP-A No. 2001-311676). Further, as another prior art regarding monitoring and detection of water leakage, there has been proposed a system which measures a water consumption in a water 5 distribution block, night time minimum water flow amount and the like so as to diagnose water leakage possibility of each water distribution block by comparison with previous measurement results (for example, see JP-A No. 2005-149280). An ultrasonic flow 10 meter which may be installed to a pipe externally is provided on any position of this system (node point, interior of manhole or fire hydrant is preferable) and with this installation position employed as a flow rate monitoring point, a possibility of the water leakage of 15 each water distribution block is diagnosed based on the total factors about the flow rate and flow direction of water passing through each monitoring point. Further, there has been proposed a water leakage determining method which compares the minimum water 20 distribution amount with a tolerable water leakage amount which is obtained when no water leakage exists in a water pipe, and determines that a water leakage exists if the minimum water distribution amount is larger than the tolerable water leakage amount (see, 25 for example, JP-A No. 2002-55019). According to this method, a sensor which converts a rotation condition of a flow rate meter to pulse signals and outputs them is -4 installed to the meter so as to collect the output signals from the sensor at a predetermined sampling interval night and day. Then, a minimum water distribution amount of the water pipe per unit time in 5 a measurement time interval is obtained from a longest time in which no pulse is inputted from the sensor of these collected data. In the water distribution pipe facility in recent years, it is provided with a water distribution 10 management system for dividing its water distribution pipe network into plural water distribution blocks (water distribution pipe network in a predetermined area), and monitoring the water distribution condition of each water distribution block. The water 15 distribution management system collects data about flow rate and pressure of distributed water, and executes abnormality detection, status monitoring, and the like. However, the water distribution management system has no function of management processing to aim at 20 improvement of the rate of effectiveness by its water leakage prevention function. As for a underground leakage of the water distribution pipe network, generally, an investigator executes a water leakage investigation (primary 25 examination) periodically and specifies a location having a high possibility of water leakage based on a result of the investigation and then, carries out a -5 detailed water leakage location specification (secondary examination) particularly at that location. On the primary investigation stage, the investigator only visits specified locations periodically and currently, which water 5 distribution block should be checked intensively has not been considered. To improve such a current status, it is preferable that information regarding the water leakage diagnosis to aim at improvement of the rate of effectiveness may be 10 provided in a water distribution management system which collects data about the flow rate and pressure of distributed water. BRIEF SUMMARY OF THE INVENTION In a first aspect, the present invention provides an 15 apparatus for analyzing water distribution information of each of a plurality of water distribution blocks to be managed, the apparatus being applied to a water distribution management system in which a water distribution pipe network for supplying pure water is divided into the plurality of 20 water distribution blocks, the apparatus comprising: a flow rate measuring means for measuring the flow rate of pure water entering each of the water distribution blocks; a pressure measuring means for measuring the pressure 25 of distributed water of each of the water distribution blocks; a minimum flow rate calculating means for calculating a night minimum flow rate of each of the water distribution blocks based on flow rate data outputted from the flow rate 30 measuring means; a water leakage amount calculating means for calculating the leakage amount of each of the water - 6 distribution blocks based on the night minimum flow rate calculated by the minimum flow rate calculating means; and an arithmetic operating means for generating information indicating a relation between the pressure and 5 the leakage amount using the pressure value measured by the pressure measuring means and the leakage amount calculated by the water leakage amount calculating means, wherein the water leakage amount calculating means assumes that the night minimum flow rate is a sum of the water 10 leakage amount and a night consumption amount so as to estimate the night consumption amount of each of the water distribution blocks to execute an arithmetic operation for estimating the water leakage amount of each of the water distribution blocks based on the night minimum flow rate. 15 In a second aspect, the present invention provides an apparatus for analyzing water distribution information of each of a plurality of water distribution blocks to be managed, the apparatus being applied to a water distribution management system in which a water distribution pipe network 20 for supplying pure water is divided into the plurality of water distribution blocks, the apparatus comprising: a flow rate measuring means for measuring the flow rate of pure water entering each of the water distribution blocks; 25 a pressure measuring means for measuring the pressure of distributed water of each of the water distribution blocks; a minimum flow rate calculating means for calculating a night minimum flow rate of each of the water distribution 30 blocks based on flow rate data outputted from the flow rate measuring means; a water leakage amount calculating means for - 6A calculating the leakage amount of each of the water distribution blocks based on the night minimum flow rate calculated by the minimum flow rate calculating means; an arithmetic operating means for generating 5 information indicating a relation between the pressure and the leakage amount using the pressure value measured by the pressure measuring means and the leakage amount calculated by the water leakage amount calculating means; a Q-H curve arithmetic operating means for calculating 10 Q-H curve information indicating a relation between a pressure value H measured by the pressure measuring means, using a pipe resistance parameter R in each of the water distribution blocks and a flow rate multiplier parameter a, and a flow rate Q measured by the flow rate measuring means; 15 and a rate-of-effectiveness estimating means for estimating the rate of effectiveness from a current amount of entering water in each of the water distribution blocks by superimposing information indicating the relation between 20 the pressure and the water leakage amount generated by the arithmetic operating means on the Q-H curve information. In a third aspect, the present invention provides an apparatus for diagnosing leakage of water in a water distribution pipe, the apparatus being applied to a water 25 distribution management system in which a water distribution pipe network for supplying pure water is divided into a plurality of water distribution blocks to be managed, the apparatus comprising: a flow rate measuring means for measuring the flow 30 rate of pure water entering each of the water distribution blocks; a minimum flow rate calculating means for calculating - 6B a night minimum flow rate of each of the water distribution blocks based on flow rate data outputted from the flow rate measuring means; a pressure measuring means for measuring a pressure of 5 distributed water of each of the water distribution blocks; a water leakage coefficient arithmetic operating means which when the night minimum flow rate calculated by the minimum flow rate calculating means is regarded as a water leakage amount of the water distribution pipe, establishes a 10 relational expression between the pressure value and the water leakage amount based on the leakage amount and the pressure value measured by the pressure measuring means and generates a leakage coefficient; a pipe information acquiring means which divides the 15 water distribution block into plural areas, and acquires pipe information including at least burying positions of the water distribution pipes for each area; a hydrostatic pressure calculating means for calculating the hydrostatic pressure value of each area 20 using the pressure value and the pipe information; and a water leakage amount calculating means for calculating the water leakage amount of each area using the relational expression between the pressure value and the water leakage amount and the hydrostatic pressure and the 25 water leakage coefficient. In a fourth aspect, the present invention provides a method of water leakage diagnosis for a water distribution pipe, the method being applied to a water distribution management system in which a water distribution pipe network 30 for supplying pure water is divided to a plurality of water distribution blocks to be managed, the method comprising the steps of: - 6C measuring a flow rate of pure water entering each of the water distribution blocks; calculating a night minimum flow rate of each of the water distribution blocks based on flow rate data measured 5 by the flow rate measuring step; measuring a pressure value of distributed water of each of the water distribution blocks; establishing a relational expression between the pressure value and a water leakage amount when the night 10 minimum flow rate calculated by the night minimum flow rate calculating step is regarded as the water leakage amount of the water distribution pipe, based on the water leakage amount and the pressure value measured by the pressure measuring means, so as to generate a leakage coefficient; 15 dividing the water distribution block into plural areas so as to obtain pipe information including at least burying positions of the water distribution pipe for each area; calculating a hydrostatic pressure of each area using 20 the pressure value and the pipe information; and calculating a water leakage amount of each area using a relational expression between the pressure value and the leakage amount and the hydrostatic pressure and the water leakage coefficient. 25 BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the 30 embodiments given below, serve to explain the principles of the invention. FIG. 1 is a block diagram for explaining the - 7 structure of an apparatus according to a first embodiment of the present invention; FIG. 2 is a diagram for explaining schematically a water distribution process and a water distribution 5 management system according to the first to third embodiments; FIG. 3 is a diagram for explaining the relation between a night minimum flow rate and a pressure according to the first embodiment; 10 FIG. 4 is a diagram showing an example of information about water consumption according to the first embodiment; FIG. 5 is a characteristic diagram showing the relation between the night minimum flow rate and the 15 pressure according to the first embodiment; FIG. 6 is a block diagram showing the structure of an apparatus according to a second embodiment; FIG. 7 is a block diagram showing the structure of an apparatus according to a third embodiment; 20 FIG. 8 is a characteristic diagram showing a relati-on between a Q-H curve and pressure- water leakage amount according to the third embodiment; FIG. 9 is a block diagram for explaining the structure of a water leakage diagnosing apparatus 25 according to a fourth embodiment; FIG. 10 is a diagram for explaining schematically a water distribution process and water distribution -8 management system according to the fourth embodiment; FIG. 11 is a diagram showing an example of table information indicating the relation between the night minimum flow rate and the pressure according to the 5 fourth embodiment; FIG. 12 is a diagram showing an example of a pipe network analysis result according to the fourth embodiment; FIG. 13 is a diagram for explaining the relation 10 between a supplied water pressure and total water leakage amount according to the fourth embodiment; FIG. 14 is a diagram showing a result of simulation by pipe network analysis according to the fourth embodiment; 15 FIG. 15 is a diagram showing a specific example of pipe information according to the fourth embodiment; FIG. 16 is a diagram for explaining a calculation method for hydrostatic pressure according to the fourth embodiment; 20 FIG. 17 is a diagram for explaining a concept on water leakage amount composition ratio according to the fourth embodiment; FIG. 18 is a diagram showing an example of water leakage distribution display according to the fourth 25 embodiment; FIG. 19 is a flow chart for explaining an operation of the water leakage diagnosing apparatus -9 according to the fourth embodiment; FIG. 20 is a diagram showing an example of data analysis on the night minimum flow rate according to the fourth embodiment; 5 FIG. 21 is a diagram showing an example of data analysis of each water distribution block about the night minimum flow rate according to the fourth embodiment; and FIG. 22 is a diagram for explaining the 10 configuration of a system according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION Hereinafter, each embodiment of the present invention will be described with reference to the 15 accompanying drawings. FIG. 2 is a diagram for explaining schematically a water distribution process and a water distribution management system for distributing pure water to consumers according to each embodiment; 20 In the water distribution process for distributing pure water to consumers through a water distribution pipe network from a water distribution reservoir 50 as shown in FIG. 2, the water distribution pipe network is divided into plural water distribution blocks 31 to 33 25 to be controlled. The water distribution management system monitors the amount of pure water entering the respective water distribution blocks 31 to 33 using - 10 flow rate meters 40A to 40D disposed at an outlet of the water distribution reservoir 50 and each intake of the respective water distribution blocks 31 to 33. The water distribution management system also 5 monitors a distributed water pressure of each of the water distribution blocks 31 to 33 using pressure gauges 41A to 41C disposed in the respective water distribution blocks 31 to 33. The water distribution management system, as described later, collects 10 measurement data about water inflow measured by the flow rate meters 40A to 40D and pressures measured by the pressure gauges 41A to 41C, and accumulates the data in a memory unit, for example, by a 1-minute cycle. 15 [First embodiment] FIG. 1 is a block diagram showing the structure of a water distribution information analyzing apparatus of a first embodiment. The water distribution information analyzing 20 apparatus is largely divided into a data control terminal 10 and a unit main body 20 as shown in FIG. 1. The data control terminal 10 is constituted of a computer including such an I/O unit as a keyboard and a display, and a database 12 including a memory unit, and 25 plant data PD collected by the aforementioned water distribution management system is inputted and accumulated in the database 12. The plant data PD - 11 contains the measurement data about the amount of water entering the water distribution blocks 31 to 33 and the pressure. The unit main body 20 is constituted of a computer 5 system (hardware and software) and includes a pressure data collecting unit 21, a night minimum flow rate collecting unit 22, a water leakage amount estimating unit 23, a database 24 and a pressure-water leakage amount arithmetic operating unit (hereinafter referred 10 to as just an arithmetic operating unit) 25. The pressure data collecting unit 21 collects pressure data 100 in the unit of a minute from the database 12 of the data control terminal 10 for each of the water distribution blocks 31 to 33. The night 15 minimum flow rate collecting unit 22 collects the flow amount data 110 in the unit of a minute from the database 12 of the data control terminal 10 for each of the water distribution blocks 31 to 33. The night minimum flow rate collecting unit 22 20 extracts a time when the amount of the entering water is the smallest in a day based on the flow amount data 110 in the unit of a minute, and selects the amount of entering water at that time as the night minimum flow rate. On the other hand, the pressure data collecting 25 unit 21 outputs the pressure data 120 at the night minimum flow rate time. Further, the water leakage amount estimating unit - 12 23 determines whether or not the night minimum flow rate should be regarded as a water leakage amount based on the night minimum flow rate 150 acquired from the night minimum flow rate collecting unit 22, and outputs 5 a water leakage amount estimation value 130. The water leakage amount estimating unit 23 estimates the water leakage amount using information about water usage with reference to the database 24 for each of the respective water distribution blocks 31 to 33. As information 10 about water consumption, preliminarily, information pieces regarding a charged water amount, divided water amount, meter non-sensed water amount, regional business consumed water amount, arbitrated reduced water amount and the like are accumulated in the 15 database 24. The arithmetic operating unit 25, as described later, establishes a relational expression (arithmetic expression) indicating the relation between the pressure and water leakage amount using the pressure 20 data 120 of the night minimum flow rate time outputted from the pressure data collecting unit 21 and the water leakage amount estimation value 130 outputted from the water leakage amount estimating unit 23, and outputs information 170 of the relational expression to the 25 data control terminal 10. Hereinafter, the operation effect of the embodiment will be described with reference to FIGS. 3 - 13 to 5 as well as FIG. 1. The night minimum flow rate collecting unit 22 extracts a time when the amount of the entering water is the smallest in a day based on the flow rate data 5 110 in the unit of a minute, and outputs night minimum flow rate data 140 which is the amount of the entering water at that time set as the night minimum flow rate. The data control terminal 10 extracts only data of a time interval having the smallest flow rate from data 10 on the amount of the entering water and its pressure of each water distribution block accumulated a certain cycle using the night minimum flow rate data 140 and pressure data outputted from the night minimum flow rate collecting unit 22 so as to generate the data 15 shown in FIG. 3. The pressure data collecting unit 21 extracts a pressure value of a selected time interval as the night minimum flow rate or a value averaged throughout a certain period (for example, an average value over an 20 hour) using the night minimum flow rate data 140 outputted from the night minimum flow rate collecting unit 22, and outputs the value as the pressure data 120. The leakage amount estimating unit 23 determines 25 whether the night minimum flow rate should be regarded as a water leakage amount using the night minimum flow rate in the unit of minute acquired from the night - 14 minimum flow rate collecting unit 22 and information about the water consumption of the database 24, and then outputs the leakage amount estimation value 130. Although it is difficult to consider that the night 5 minimum flow rate is equal to the water leakage amount if the accumulated data is stored in the unit of hour, it may be considered that the night minimum flow rate is as equal to the water leakage amount as possible if the data is accumulated in the unit of minute or 10 second. When the scale of a target water distribution block is large, it is difficult to grasp a downtime and therefore, it is defined that the night minimum flow rate is equal to the water leakage amount plus the night consumption amount by estimating a certain 15 consumption amount and then, the night consumption amount is estimated from previous data about the effective recovery rate, or the like. Then, the leakage amount may be assumed based on the estimated value. 20 More specifically, the water leakage amount estimating unit 23 may calculate the water leakage amount, for example, every two months using information about the water consumption of the database 24 so as to estimate the night consumption amount from that value. 25 Consequently, the water leakage amount 130 may be estimated from the night minimum flow rate 150. FIG. 4 is a diagram showing an example of information about - 15 the water consumption accumulated in the database 24. Next, the arithmetic operating unit 25 establishes a relational expression (model) showing the relation between the pressure and water leakage amount using the 5 pressure data 120 and the water leakage amount estimation value 130 of the night minimum flow rate time. It has been experimentally confirmed that a relation shown in an expression (1) below exists between the pressure and water leakage amount of each 10 of the water distribution blocks 31 to 33 (see "Analysis and Design of Water Distribution Pipe Network", written by TETSUO TAKAKUWA, published by MORIKITA SHUPPAN, 1978). 15 L = C(E - G)a ... (1) Where L is a water leakage amount [m 3 /s], C is a coefficient depending on the shape and area of an extension or a leaking hole in a water branch pipe and water supply pipe, E is an energy level [m] of a pipe 20 network node, G is a height of the pipe center [m), and a is an experimental multiplier, for example, 1.15. Here, G corresponds to an installation place of the pressure gauge, and E-G correspond to measurement values of the pressure gauges 41A to 41C. 25 The arithmetic operating unit 25 outputs information 170 indicating the relational expression shown in the expression (1) and parameter C to the data control terminal 10. The data control terminal 10 may - 16 diagnose a water leakage of each of the respective water distribution blocks 31 to 33 based on the information 170 outputted from the arithmetic operating unit 25. According to the embodiment, the data control 5 terminal 10 executes water leakage diagnosis based on specifically the parameter C in the information 170 outputted from the arithmetic operating unit 25. The arithmetic operating unit 25 determines the parameter C according to a least squares method or the 10 like using the data shown in FIG. 3. This parameter C corresponds to an index indicating the water leakage characteristic of each of the water distribution blocks 31 to 33. According to the aforementioned expression (1), even in the same pipe network within the water 15 distribution block, as the pressure (E to G) increases, the water leakage amount (L) increases. Thus, the characteristic about the water leakage in the water distribution block may be grasped using the value of the parameter C excluding an influence of the pressure. 20 That is, the data control terminal 10 may evaluate the water leakage condition of each of the water distribution blocks 31 to 33 based on the parameter C contained in the information 170 outputted from the arithmetic operating unit 25. 25 FIG. 5 is a characteristic diagram showing the relation between the night minimum flow rate and pressure within the water distribution block. As shown - 17 in FIG. 5, a night minimum flow rate 500 indicates a trend of increase (530) because a reduction valve is released since a certain period so that distributed water pressure 520 is increased. However, if seeing 5 the trend of the parameter C (510) obtained from a calculation by substituting the night minimum flow rate into the water leakage amount L of the expression (1), it is evident that a trend of decrease (540) exists. That is, the parameter C has been decreasing after the 10 pressure is increased although the night minimum flow rate is increased. Thus, in the water leakage diagnosis of the embodiment, a diagnostic result that the locations and scale of water leakage within the water distribution 15 block have been decreasing although the night minimum flow rate, for example, is increased by introducing not only the night minimum flow rate in the water distribution block but also the parameter C which may take a pressure state at that time into account. 20 [Second embodiment] FIG. 6 is a block diagram showing the structure of a water distribution information analyzing apparatus according to a second embodiment. Like reference numerals are attached to the same components as the 25 water distribution information analyzing apparatus shown in FIG. 1 described above, and descriptions thereof are omitted.

- 18 The water distribution information analyzing apparatus of the present embodiment has a pipe renewal construction evaluation unit 26 for evaluating a pipe renewal construction based on the information 170 5 outputted from the arithmetic operating unit 25. The pipe renewal construction means a construction for pipe renewal to aim at blocking a water leakage in each of the water distribution blocks 31 to 33. The pipe renewal construction evaluation unit 26 10 evaluates a given construction based on the parameter C contained in the information 170 at a current time by referring to a database 27 in which the history information pieces of previous pipe renewal construction are accumulated in advance, more 15 specifically analyzes the water leakage reduction effect of the pipe renewal construction statistically. The pipe renewal construction evaluation unit 26 outputs information 180 indicating an evaluation result (analysis result) to the data control terminal 10. 20 More specifically, the pipe renewal construction evaluation unit 26 verifies the content of a construction in which the number of the parameters C is reduced by referring to the database 27 so as to grasp which construction is effective for water leakage 25 countermeasure and outputs the evaluation result 180 necessary for determining whether or not the same construction should be progressed. The content of - 19 construction mentioned here is the information indicating for example, which pipe type is exchanged with which pipe type or the like, and accumulated in the database 27. 5 The data control terminal 10 may use the information indicating the evaluation result to application of data for water leakage preventive project by grasping which water leakage affected the rate of effectiveness of the entire water distribution 10 block dominantly to set focused areas for the water leakage investigation. If speaking of a specific example, it is evident that if, for example, a construction for replacing a cast iron pipe with a stainless pipe as the type of the water pipe is carried 15 out, the water leakage reduction effect of that construction is high. On the other hand, the pipe renewal construction evaluation unit 26 outputs a list indicating which event (for example, construction) occurred at a timing 20 when the parameter C value was increased with reference to the database 27 so as to output the evaluation result 180 which allows to grasp a reason for the increase of the water leakage amount within the water distribution block. In other words, the pipe renewal 25 construction evaluation unit 26 outputs information indicating the reason why the water leakage condition is worsened when the parameter C is increased, as the - 20 evaluation result 180. The data control terminal 10 may classify relatively into a water distribution block having a high water leakage reduction effect and a water 5 distribution block having a low water leakage reduction effect, based on a result of comparison of the parameters C for each of the respective water distribution blocks 31 to 33. [Third embodiment] 10 FIG. 7 is a block diagram showing the structure of a water distribution information analyzing apparatus according to a third embodiment. Like reference numerals are attached to the same components as the water distribution information analyzing apparatus 15 shown in FIG. 1, and descriptions thereof are omitted. The water distribution information analyzing apparatus of the present embodiment includes a rate-of effectiveness estimating unit 28, a pressure control introduction evaluation unit 29 and a Q-H curve 20 arithmetic operating unit 30. The rate-of effectiveness estimating unit 28 estimates the rate of effectiveness based on the information 170 outputted from the arithmetic operating unit 25. The pressure control introduction evaluation unit 29 evaluates a 25 pressure control introduction effect (information of the water leakage effect) 220 based on an estimated rate-of-effectiveness (information) outputted from the - 21 rate-of-effectiveness estimating unit 28. The Q-H curve arithmetic operating unit 30 calculates Q-H curve information 230 described later based on data 200 containing measurement values about the flow rate and 5 pressure collected from the database 12 of the data control terminal 10, and outputs the information 230 to the rate-of-effectiveness estimating unit 28. The rate-of-effectiveness estimating unit 28, the pressure control introduction evaluation unit 29, and the Q-H 10 curve arithmetic operating unit 30 output the information pieces 210, 220 of each of the respective water distribution blocks 31 to 33 to the data control terminal 10. Hereinafter, the operation effect of the rate-of 15 effectiveness estimating unit 28, the pressure control introduction evaluation unit 29 and the Q-H curve arithmetic operating unit 30 will be described. The relation between the flow rate of the water distribution block and the pressure in the water 20 distribution block may be expressed as a relational expression in which cc and R are introduced into a Hezen Williams' expression as shown in an expression (2) below. The Hazen Williams' expression is an expression 25 for calculating the lost water amount (corresponds to the water leakage amount) of a single pipe or an arithmetic expression with virtual pipe total length L, - 22 flow meter indicated value Q, flow velocity count C and pipe diameter D as parameters. Further, sometimes, the lost water amount may be increased even under the same flow rate condition because the pipe network is not 5 constituted of a single pipe system, and this expression may be expanded to Hazen Williams' approximate expression by adding a flow rate correction coefficient a for increasing the apparent flow rate as a parameter obtained by the least squares method. That 10 is, the flow rate and pressure of the pipe network may be approximated by a single virtual pipe system according to this Hazen Williams' approximate expression. In this case, a pipe system having a reduction in pressure is provided with the flow rate 15 correction coefficient a because the lost water amount may not be expressed unless the flow rate is increased virtually. The relational expression (2) using such Hazen Williams' approximate expression is as follows. 20 Hh -H=RQa .--(2) Where Hh is an intake side pressure [m] of a water distribution block, H is pressure gauge indicated value plus pressure gauge installation height [m], Q is a 25 flow meter indicated value [m 3 /s), R is a pipe resistance parameter, and a is a flow rate multiplier parameter corresponding to the flow rate correction coefficient.

- 23 The Q-H curve arithmetic operating unit 30 substitutes measurement values H, Q about the pressure and flow rate contained in the data 200 collected from the database 12 of the data control terminal 10 into 5 the aforementioned relational expression (2) so as to obtain a, R and Hh using the least squares method, and then determines an approximate expression from the obtained values. Hereinafter, the relational expression (2) is called Q-H curve (information 230). 10 FIG. 8 is a diagram showing the characteristic in which the Q-H curve (information 230) and the relation (information 170) between the pressure and flow rate are superimposed. In FIG. 8, a reference numeral 810 designates a Q-H curve (information 230 expressed by 15 the relational expression (2)), and a reference numeral 820 designates a relation (information 170 expressed by the aforementioned expression (1)) between the pressure and flow rate. A reference numeral 800 means live data which are measurement values of the pressure and flow 20 rate. The rate-of-effectiveness estimating unit 28 calculates an estimated pressure value from a current flow rate based on the Q-H curve (information 230). Further, the rate-of-effectiveness estimating unit 28 25 estimates a water leakage rate from the relation between the pressure and leakage amount based on the aforementioned expression (1) of the information 170.

- 24 Thus, the rate-of-effectiveness estimating unit 28 estimates, by calculating the estimated water leakage amount under an operating condition at the flow rate of a certain water distribution block, the rate of 5 effectiveness at that operating point. That is, the rate-of-effectiveness estimating unit 28 calculates and outputs the estimated rate-of-effectiveness 210 as shown with a reference numeral 830 in FIG. 8. The data control terminal 10 may execute daily 10 water operation from viewpoints of reduction of water leakage amount based on the estimated rate-of effectiveness 210 calculated by the rate-of effectiveness estimating unit 28. Because generally, the amount of flow entering a water distribution block 15 is affected by consumer's life pattern, it may not be controlled. Thus, conventionally, the rate of effectiveness may be confirmed only, for example, once every two months. To the contrary, because the estimated rate-of-effectiveness may be obtained by the 20 rate-of-effectiveness estimating unit 28 of the embodiment, the rate of effectiveness may be confirmed in the unit of every day also. The pressure control introduction evaluation unit 29 evaluates the pressure control introduction effect 25 (information on water leakage reduction effect) 220 based on the estimated rate-of-effectiveness 210 calculated by the rate-of-effectiveness estimating unit - 25 28 and outputs the evaluated value to the data control terminal 10. If the Q-H curve 810 shown in FIG. 8 is a curve downward-sloping extremely while the pressure water leakage amount curve 820 is a curve upward 5 sloping extremely as compared with other water distribution block, it is evident that the effect of reduction of the water leakage amount is increased by executing the pressure control. That is, from viewpoints of improvement of the rate of effectiveness, 10 an introduction effect when the pressure control is introduced may be estimated. Thus, the data control terminal 10 may achieve a reduction of the water leakage amount by executing the pressure control from the pressure control introduction effect 220 resulted 15 from the pressure control introduction evaluation unit 29. In the meantime, as a modification of each embodiment, the water distribution information analyzing apparatus having a water distribution block 20 renewal unit may be used. If the water distribution block is changed at a certain period, the water distribution block renewal unit automatically updates a range closed along a pipe network leading from a water distribution block water entering position by inputting 25 a record of operating gate valves in the pipe, as a new water distribution block. As described above, the water distribution - 26 information analyzing apparatus may distinguish a water leakage affected by the pressure from a water leakage affected, by a pipe condition by introducing the aforementioned parameter C instead of diagnosing the 5 water leakage amount of each water distribution block with only the night minimum flow rate, so as to diagnose the water leakage amount of each water distribution block. Further, the daily operation of the water distribution facility may be improved based 10 on the effect of the pipe renewal construction and estimated rate-of-effectiveness. In conclusion, in case where the apparatus is applied to the water distribution management system of the waterworks facility, it may execute data analysis regarding the 15 water leakage diagnosis using process data (night minimum flow rate, pressure, flow rate, and the like) collected and accumulated by the water distribution management system. Consequently, the present invention may provide information necessary for countermeasure 20 for improvement of the rate of effectiveness. [Fourth embodiment] A forth embodiment concerns a water leakage diagnosing apparatus for the water distribution pipe capable of specifying a detailed water leakage location 25 within a water distribution block, making a water leakage investigation (primary examination) project, and making a pipe renewal plan which secures a cost - 27 effectiveness. The apparatus is a water leakage diagnosing apparatus for the water distribution pipe which may not only analyze the night minimum flow rate in the unit of a water distribution block of the water 5 distribution pipe network but also estimate a water leakage location of a specified area (for example, a specified mesh on map information) within the water distribution block. FIG. 10 is a diagram for explaining schematically 10 the water distribution process and water distribution management system for distributing pure water to consumers 42 according to the present embodiment. As shown in FIG. 10, in the embodiment, it is assumed a water distribution process in which pure 15 water is supplied to a water distribution block corresponding to water distribution pipe networks 34-1 to 34-16 from a water distribution reservoir 50. This water distribution block is a single water distribution block provided when a large scale water distribution 20 pipe network is divided into plural areas (water distribution blocks). The water distribution management system monitors the amount of entering water from the water distribution reservoir 50 by means of the flow rate 25 meter 40 disposed at an intake of the water distribution block. Further, the water distribution management system monitors the pressure of distributed - 28 water within the water distribution block using the pressure gauge 41 disposed within the water distribution block. As described later, the water distribution management system collects measurement 5 data of the amount of entering water measured with the flow rate meter 40 and the pressure values measured by the pressure gauge 41, and accumulates the data in the monitor database (DB) 12. Numerals in circles in FIG. 10 designate node 10 numbers indicating node points of plural water distribution pipes 34-1 to 34-16 (sometimes expressed as just pipe). (Water Leakage diagnosing apparatus) FIG. 9 is a block diagram showing the structure of 15 a water leakage diagnosing apparatus for use in the water distribution management system of the embodiment. The water leakage diagnosing apparatus corresponds to a water leakage distribution estimating apparatus for estimating a water leakage distribution in the water 20 distribution block. As shown in FIG. 9, the water leakage diagnosing apparatus is largely divided into the data control terminal 10 and a system main body. The data control terminal 10 is constituted of the computer 11 including 25 I/O units such as a keyboard and a display, and the monitor database (DB) 12 including a memory unit. As described above, the monitor database 12 accumulates - 29 measurement data about the amount of entering water measured by the flow rate meter 40 and the pressure values measured by the pressure gauge 41. The system main body is constituted of a computer 5 system (hardware and software) and includes the pressure data collecting unit 21 and the night minimum flow rate collecting unit 22. The night minimum flow rate collecting unit 22 extracts a time when the amount of entering water is the smallest in a day based on the 10 flow amount data 110 accumulated in the monitor database 12, and selects the amount of entering water at that time as the night minimum flow rate. The night minimum flow rate collecting unit 22 collects the flow rate data 110 by a cycle of once a day, and accumulates 15 a selected night minimum flow rate data 320 in the monitor database 12. On the other hand, the pressure data collecting unit 21 extracts a pressure value of a time interval selected as the night minimum flow rate or a value 20 averaged in a certain period (for example, a value averaged over an hour) using the night minimum flow rate data 320 outputted from the night minimum flow rate collecting unit 22, and outputs the value as the pressure data 330 at the night minimum flow rate time. 25 The pressure data collecting unit 21 collects the pressure data 330 by a cycle of once a day. The system main body extracts only data of a time - 30 when the flow rate is the smallest in a day from the flow rate data and pressure data of the accumulated water distribution block, for example, by a cycle of once a day, and generates a table information piece as 5 shown in FIG. 11. Further, the system main body includes a water leakage coefficient arithmetic operating unit 15, a water leakage distribution display unit 16, a leakage estimation unit 17, a pipe information extracting unit 10 18, a pipe information database (DB) 14, a hydrostatic pressure calculating unit 13, the water consumption database (DB) 24, a total demand and water leakage amount calculating unit (hereinafter referred to as water leakage amount calculating unit) 19, and a pipe 15 network analyzing unit 60. The water leakage amount calculating unit 19 calculates a water leakage amount 410 of a given water distribution block based on the total demand (amount of entering water of a water distributing block) of a day, 20 water charge data checked by a cycle of once every two months and the like, using information accumulated in the water consumption database 24. As information about water consumption, preliminarily, information pieces regarding a charged water amount, divided water 25 amount, meter non-sensed water amount, regional business consumed water amount, arbitrated reduced water amount, and the like are accumulated in the water - 31 consumption database 24. The water leakage coefficient arithmetic operating unit 15 establishes a relational expression indicating the relation between the pressure and leakage amount of 5 each water distribution block using the night minimum flow rate data 300 outputted from the night minimum flow rate collecting unit 22, the pressure data 330 at the night minimum flow rate time and the leakage water data 410, and determines a water leakage coefficient C 10 (parameter regarding the water leakage amount) described later. The pipe network analyzing unit 60 executes pipe network analysis processing in the water distribution block using the water leakage coefficient C from the 15 water leakage coefficient arithmetic operating unit 15 and the information accumulated in the water consumption database 24. More specifically, the pipe network analyzing unit 60 estimates a water leakage amount of each node point of the pipes 34-1 to 34-16 20 within the water distribution block based on the effective water pressure of each node point and the water leakage coefficient C, and outputs a water consumption amount (night water consumption amount data 400) of a time interval having the night minimum flow 25 rate. The pipe network analyzing unit 60 estimates a total water leakage amount of the water distribution block by executing pipe network analysis calculation at - 32 a time of a specified terminal pressure control, generates information 440 for evaluation of the water leakage amount reduction effect at the time when the terminal pressure control is introduced, and then 5 outputs the information to the data terminal 10. The pipe information extracting unit 18 extracts pipe information 390 which is a cause for a change of the leakage coefficient C based on the amount of change of the leakage coefficient C from the leakage 10 coefficient arithmetic operating unit 15 and the pipe information accumulated in the pipe information database 14. That is, the pipe information extracting unit 18 monitors the change of the pipe information at a timing when the leakage coefficient C is changed, and 15 outputs the information 390 which indicates its factor variable. The pipe information pieces indicating the specification of the pipes 34-1 to 34-16 buried in the ground within the water distribution block are 20 accumulated in the pipe information database 14. The pipe information is information pieces about, for example, burying positions, burying period, material, diameter, pipe extension, number of hydrants and the like of each pipe, or information about plural areas 25 (meshes on map data) dividing the water distribution block as described later. The hydrostatic pressure calculating unit 13 - 33 calculates hydrostatic pressure 370 of each mesh based on a typical ground elevation (altitude) of each area (mesh on the map data) accumulated in the pipe information database 14 and a pressure value at the 5 night minimum flow rate time from the pressure data collecting unit 21. The water leakage estimation unit 17 estimates water leakage composition ratio information 380 based on the pipe information (factor variable) 390 extracted 10 by the pipe information extracting unit 18 and the hydrostatic pressure (typical pressure value) 370 of each mesh calculated by the hydrostatic pressure calculating unit 13. The water leakage composition ratio information 380 is information about allocation 15 of the leakage composition ratios on respective meshes, with distribution of the pipe extension and the quantity of pipes, which are causes extracted by the pipe information extracting unit 18 adopted as the leakage composition ratio. The water leakage 20 estimation unit 17 calculates the water leakage composition ratio so that a difference between the hydrostatic pressure (typical pressure value) of each mesh and the water leakage amount of the entire water distribution block to be a minimum by repeated 25 arithmetic operation. A water leakage distribution display unit 16 outputs display information for displaying a water - 34 leakage amount estimation distribution, calculated based on the water leakage composition ratio information 380 from the water leakage estimating unit 17, the water leakage coefficient C from the water 5 leakage coefficient arithmetic operating unit 15 and the hydrostatic pressure (typical pressure value) 370 of each mesh calculated by the hydrostatic pressure calculating unit 13, on map data corresponding to the water distribution block, to the data control terminal 10 10. In the meantime, the map data corresponding to the water distribution block is information contained in the pipe information accumulated in the pipe information database 14. (Operation effect) 15 Hereinafter, the operation effect of the water leakage diagnosing apparatus of the embodiment will be described with reference to FIGS. 12 to 21. FIG. 19 is a flow chart for explaining the outline (diagnostic procedure) of the operation of the water 20 leakage diagnosing apparatus of the embodiment. Hereinafter, the operation of the water leakage diagnosing apparatus will be described. First, the water leakage amount calculating unit 19 calculates the water leakage amount 410 of a given 25 water distribution block based on the total demand (amount of entering water of a water distribution block) of a day, water charge data checked by a cycle - 35 of once every two months and the like, using the information accumulated in the water consumption database 24 (step Sl). As the calculation method of the water leakage amount calculating unit 19, the data 5 collection method using information pieces about water consumption accumulated in the database 24 as shown in FIG. 4 is used. Generally, it is difficult to consider that the night minimum flow rate and the water leakage amount 10 are equal to each other here. However, it may be estimated that the water consumption at night is small if the scale of the water distribution block (water distribution area) is small, therefore it is considered that the water leakage amount is equal to the night 15 minimum flow rate. If the scale of the water distribution block is large, the water leakage amount may be assumed based on a night consumption amount estimated from previous data about the effective recovery rate, by defining that the night minimum flow 20 rate is equal to the water leakage amount plus the night consumption amount, with a specific amount of consumption at night assumed. That is, because the night minimum flow rate contains the water leakage amount and the night water consumption amount, it is 25 expressed by a following expression (3). Qmin =L+U - (3) Where Qmin indicates the night minimum flow rate - 36 [L/sec), L indicates the water leakage amount [L/sec], and U indicates the night water consumption amount [L/sec]. In the expression (3) above, the night water 5 consumption amount U is obtained by converting the water leakage amount of a day based on the water leakage amount of a cycle of two months obtained by the water leakage amount calculating unit 19. Therefore, the water leakage amount of the water distribution 10 block may be monitored by monitoring the night minimum flow rate. In the meantime, as the method for determining the night water consumption amount U under the aforementioned expression (3), other than a method for dividing the night water consumption to meet the 15 water distribution trend of a day according to the water works check data of two months, there are available a method for estimating the water leakage amount of a time interval having the night minimum flow rate using the pipe network analyzing method. This 20 method will be described below. The water leakage coefficient arithmetic operating unit 15 establishes a relational expression (model) indicating the relation between the pressure value and the leakage amount of each water distribution block 25 based on the pressure data 330 and the water leakage amount data 410 at the night minimum flow rate time. Here, the pressure data collecting unit 21 outputs a - 37 pressure value of a time interval selected as the night minimum flow rate or a value average over a certain period (for example, a value averaged over an hour) as the pressure data 330 at the night minimum flow rate 5 time (step S2). Generally, it has been confirmed experimentally that a relation shown by an expression (4) below exists between the pressure value and the water leakage amount within the water distribution block (see "Analysis and 10 Design of Water Distribution Pipe Network", written by TETSUO TAKAKUWA, published by MORIKITA SHUPPAN, 1978). Li =Cihik ... (4) Where Li indicates a leakage amount [L/sec] at a 15 node point i, Ci indicates a coefficient depending on the pipe extension, diameter and the shape and area of the water leaking hole at the node point i, hi indicates an effective water pressure (m] at the node point I, and k is an experimental multiplier, for 20 example, 1.15. The node point is expressed with a numeral in a circle (connecting point of a pipe in a pipe network model) in FIG. 2. In this Figure, i is 1 to 13. The water leakage coefficient arithmetic operating 25 unit 15 determines a leakage coefficient C (parameter regarding the leakage amount) described later by introducing the expression (4) (step S3). According to the embodiment, if the entire water distribution block - 38 is assumed as a single pipe and the aforementioned expression (4) is considered about the node point 13, the water leakage coefficient C at the water distribution block may be obtained because the 5 measurable pressure value is found at only the node point 13. That is, the water leakage coefficient arithmetic operating unit 15 determines the water leakage coefficient C shown in an expression (5) below according to the least squares method based on the 10 extracted data indicated in FIG. 11. 1N C= jCi --- (5) N Ni=1 Where N indicates the total number of the node points (13 here). 15 If the water leakage coefficient C is assumed to be an index which indicates the water leakage characteristic of the water distribution block, the value of the water leakage coefficient C from which influences of pressure is excluded enables the 20 characteristic of the water leakage within the water distribution block to be grasped, because the water leakage amount increases as the pressure increases even in the same pipe network. That is, according to the embodiment, the water leakage diagnosis of the water 25 distribution block and diagnosis of an aged pipe may be carried out by introducing the parameter (water leakage coefficient C) capable of taking not only the night - 39 minimum flow rate but also the pressure condition at that time into account. Further, the introduction of the water leakage coefficient C enables the water leakage amount of each 5 node point to be estimated by applying the pipe network analysis. Consequently, a water consumption of a time interval having the night minimum flow rate may be specified at a high precision. That is, the pipe network analyzing unit 60 executes the pipe network 10 analysis processing for the interior of the water distribution block using the water leakage coefficient C from the water leakage coefficient arithmetic operating unit 15 and information pieces accumulated in the water consumption database 24. More specifically, 15 the pipe network analyzing unit 60 estimates the water leakage amount of each node point of the respective pipes 34-1 to 34-16 within the water distribution block based on the effective water pressure of each node point and the water leakage coefficient C, and outputs 20 a water consumption amount (night water consumption amount data 400) of a time interval having the night minimum flow rate. The pipe network analyzing unit 60 also estimates the total water leakage amount of the water distribution block by executing the pipe network 25 analytic calculation at a time when the terminal pressure is controlled to a particular level, generates the information 440 which enables the water leakage - 40 amount reduction effect at the time of introduction of the terminal pressure control to be evaluated, and then outputs the information to the data control terminal 10. 5 FIG. 12 is a diagram showing an example of a pipe network analytic result by the pipe network process shown in FIG. 10. It is assumed that the water leakage amount as well as the water demand of each node point are included. By introducing the water leakage 10 coefficient C shown in the aforementioned expression (5) as shown in FIG. 12, the water leakage amount distribution of each node point may be obtained. The water leakage amount of each node point affects the effective water level of each node point. Further, the 15 effective water level of each node point affects the supplied water pressure (water level of the water distribution reservoir 50) and the node point demand amount. FIG. 13 is a diagram showing the relation between 20 the supplied water pressure and the total water leakage amount. A dotted line 60 in FIG. 13 indicates that the terminal pressure is a limit point of the tolerable water pressure. Further, when P is 1, it indicates that the total water amount of the demand and leakage 25 amount is maximum. Because the relation among the leakage amount, the supplied water pressure and the node demand amount is substantially in a proportional - 41 relation, an expression (6) below is established. L=0iH+2P+aL3 ---(6) Where H indicates a supplied water pressure [m], P 5 indicates a demand ratio when a demand for the maximum water amount is expressed as 1, and ci (i = 1, 2, 3) is a parameter. That is, a water leakage amount of a time unit when [ is changed may be estimated from the aforementioned expression (6). Consequently, the water 10 leakage amount of the time interval having the night minimum flow rate may be estimated and the night water consumption amount U indicated by the expression (3) may be specified at a high precision. FIG. 14 is a diagram showing a simulation result 15 by pipe network analysis. In FIG. 14, a reference numeral 70 indicates a demand pattern. A reference numeral 71 indicates a water leakage amount when the terminal pressure is controlled to a specified level. A reference numeral 72 indicates a difference 20 corresponding to the water consumption amount. Consequently, the water leakage amount reduction effect of a case where the terminal pressure is controlled to a specified level may be considered preliminarily by such a simulation. 25 Next, processing of the hydrostatic pressure calculating unit 13 (step S5) and the pipe information extracting unit 18 (step S6) will be described. The pipe information extracting unit 18 and the - 42 hydrostatic pressure calculating unit 13 use the pipe information pieces accumulated in the pipe information database 14. The pipe information pieces indicating the specifications of the pipes 34-1 to 34-16 buried in 5 the ground within the water distribution block are accumulated in the pipe information database 14. The pipe information is information pieces about, for example, burying positions, burying period, material, diameter, pipe extension, number of hydrants and the 10 like of each pipe. The pipe information is information controlled and arranged for each of plural areas (meshes on the map data) which divides the water distribution block (step S4), as shown in FIG. 15. The pipe information extracting unit 18 extracts 15 the pipe information 390 which is a cause for a change of the water leakage coefficient C based on the amount of the change of the water leakage coefficient C from the water leakage coefficient arithmetic operating unit 15 and the pipe information pieces accumulated in the 20 pipe information database 14. That is, the pipe information extracting unit 18 monitors changes of the pipe information by a timing when the water leakage coefficient C is changed, calculates the ratio of each mesh, and extracts the pipe information changed by the 25 pipe renewal construction and its change amount (step S6). On the other hand, a typical pressure of each mesh - 43 needs to be determined to estimate the water leakage amount. If a pressure gauge corresponding to each mesh is installed, its measured value is employed. Otherwise, in the embodiment, the hydrostatic pressure 5 370 of each mesh is calculated by means of the hydrostatic pressure calculating unit 13. That is, the hydrostatic pressure calculating unit 13 calculates the hydrostatic pressure 370 of each mesh based on the typical ground elevation (altitude) of each area 10 accumulated in the pipe information database 14 and the pressure value (pressure data 310) at the night minimum flow rate time from the pressure data collecting unit 21. Generally, the pressure value at the night minimum flow rate time may be considered substantially equal to 15 the hydrostatic pressure. Thus, it may be assumed that the typical pressure value of each mesh depends on a difference of the altitude. If there exists an error between the difference of the altitude and the pressure value at the night 20 minimum flow rate time, it may be corrected. Hereinafter, this situation will be described with reference to FIG. 16. For example, if a sum (dynamic water level) of the altitude of the water distribution reservoir 50 and the 25 effective water level is 55m, as shown in FIG. 16, little water flows at night. Thus, the effective water level of a mesh having a typical altitude of 15m may be - 44 assumed to be 40m. However, if there exists a divergence between a pressure measurement value of the mesh in which a pressure gauge is installed and the difference of the altitude from the dynamic water level 5 of the water distribution reservoir 50, that difference is applied to other meshes for a correction. This correction amount may be calculated from "correction amount = pressure measurement value - (dynamic level of the water distribution reservoir - altitude of a 10 pressure gauge installation position)". Next, the water leakage estimating unit 17 extracts a factor for the change of the water leakage amount based on results of processing of step S3 and step S6 (step S7). That is, the water leakage 15 estimating unit 17 calculates a water leakage composition ratio 380 so that the difference between the hydrostatic pressure (typical pressure value) of each mesh and the water leakage amount of the entire water distribution block to be a minimum by repeated 20 arithmetic operation every two months. The water leakage composition ratio information 380 is information about allocation of the leakage composition ratios on respective meshes, with distribution of the pipe extension and the quantity of pipes, which are 25 causes extracted by the pipe information extracting unit 18, adopted as the leakage composition ratio. The water leakage distribution display unit 16 - 45 outputs display information for displaying a water leakage amount estimation distribution, calculated based on the water leakage composition ratio information 200 from the leakage estimating unit 17, 5 the water leakage coefficient C from the water leakage coefficient arithmetic operating unit 15 and the hydrostatic pressure (typical pressure value) 370 of each mesh calculated by the hydrostatic pressure calculating unit 13, on the map data corresponding to 10 the water distribution block, to the data control terminal 10 (steps S8, S9). FIG. 17 is a diagram showing the concept on the water leakage amount composition ratio. The water leakage amount of the water distribution block may be 15 calculated from the effective recovery rate originating from water works check data or the night minimum flow rate. The parameter (water leakage coefficient) C indicated in the aforementioned expression (5) is calculated based on the value. The water leakage 20 amount of each mesh may be calculated based on the parameter and the effective water pressure of each mesh number. However, the parameter C indicated in the expression (5) is a parameter in a case where an interval between the flow rate meter 40 and the 25 pressure gauge 41 shown in FIG. 10 is regarded as a single pipe. For the reason, the total sum of the water leakage amounts of the respective mesh numbers - 46 does not coincide with the water leakage amount in the water distribution block. Thus, according to the embodiment, the distribution of the water leakage amount of each mesh 5 is grasped by selecting the ratio (composition ratio) constituting the water leakage appropriately as well as the pressure. It is important to determine the composition ratio so that a difference between the water leakage amount of the entire water distribution 10 block and the total sum of the water leakage amounts of the respective mesh numbers to be a minimum, from the pipe information controlled as shown in FIG. 15. A composition ratio which minimizes an error relative to the water leakage amount in the water distribution 15 block is determined by using, for example, a pipe burying period ratio, a pipe extension ratio, a corroded old pipe ratio and the like. In the meantime, the water leakage distribution display unit 16 outputs a water leakage amount 20 estimating value calculated based on the obtained water leakage amount composition ratio, the water leakage coefficient C and the typical pressure (hydrostatic pressure) of each mesh as shown in FIG. 18, onto a map in a state in which it is highlighted. FIG. 18 is an 25 output image or a display example of the water leakage distribution of each mesh 80. Such a water leakage distribution display makes possible assistance for - 47 water leakage investigation work and application of efficient pipe renewal project. Further, an example of data analysis about the night minimum flow rate by the night minimum flow rate 5 collecting unit 22 will be described with reference to FIGS. 20 and 21. FIG. 21 concerns a case where the data about the amount of entering water of the water distribution block may be collected by an earlier cycle. FIG. 21 is a diagram which compares a case of a 10 1-minute cycle with a case of 5-second cycle. As shown in FIG. 21, it is evident that a minimum value differs between the minimum flow rate of the 1-minute cycle and the minimum flow rate of the 5-second cycle as compared with a case where data of a 15 specified time considered to be the night minimum flow rate is extracted. That is, it is important to extract not a flow rate at any specified timing in any data collection cycle but the minimum flow rate of a day, and a probability of grasping a time interval in which 20 no water is consumed is intensified by collecting the data by an earlier cycle. FIG. 21 shows a case where certain five blocks are analyzed. As compared with a case of extracting the flow rate at a specified timing in the 1-minute cycle, 25 a flow rate smaller by about 61% may be grasped by extracting the minimum flow rate in the 5-second cycle. When the minimum flow rate is extracted by the 1-minute - 48 cycle and the 5-second cycle, the 5-second cycle may grasp a flow rate smaller by about 15%. Therefore, the night minimum flow rate collecting unit 13 of the embodiment may take data in directly not by a data 5 cycle accumulated in the monitor database 12 but by an earlier cycle than the one collected by the monitor system. The embodiment may realize a water leakage diagnosing apparatus for the water distribution pipe 10 which is applicable for a water distribution management system for managing the water distribution pipe network for supplying pure water by dividing into plural water distribution blocks, the water leakage diagnosing apparatus being capable of estimating a leakage 15 location in each mesh of the water distribution block as well as analyzing the night minimum flow rate of each water distribution block of the water distribution pipe network. Thus, the water leakage location may be estimated 20 not by a water distribution block but by the unit of each drawing (mesh) controlled on the map system, by taking the pipe burying condition and water consumption data (amount of charged water and the like) into account. That is, a change of the night minimum flow 25 rate and a factor which is originated from the change are extracted from the pipe information, and a distribution indicating in which area in the water - 49 distribution block the water leakage amount is large is estimated based on the extracted factor. Consequently, a water leakage investigation schedule (primary examination) and a pipe renewal project which secures a 5 cost effectiveness may be built up. [Fifth embodiment] FIG. 22 is a block diagram showing the configuration of a system according to a fifth embodiment. 10 As shown in FIG. 22, the system of the present embodiment includes each water distribution block connected to a trunk line 614, an automatic checking system 616, a water distribution management system 606, and an administrative system 600. Each water 15 distribution block is provided with a water leakage detector 615. In the meantime, description of the water leakage diagnosing apparatus is omitted since the same apparatus as the fourth embodiment is employed. The administrative system 600 includes an 20 administrative server 601, an I/O terminal 602, a monitor/data analyzing terminal 603, and a router 604. The water distribution management system 606 includes a mapping system 607, a router 608, a data input terminal 609, a server 610, a monitor terminal 611, an 25 information database 612, and a radio sensor module 613. The administrative system 600 and the water distribution management system 606 are connected to a - 50 public line or a dedicated line 605 via the respective routers 604, 608. The embodiment concerns a system for collecting data necessary for water leakage distribution 5 estimation efficiently by introducing the automatic checking system 616 using radio communication. Consequently, personnel cost required for meter check work may be reduced and further, a demand for water may be measured not every two months but by an earlier 10 cycle, whereby making possible water leakage distribution estimation at a high precision. In case of collecting data by radio, an investigator needs to visit a neighboring place. However, for example, by cruising around an area with a 15 vehicle loaded with a receiver, the water work check data of the neighboring place may be collected. It is permissible to always collect a result of water leakage judgment by radio with the water leakage detectors 615 installed at a fire hydrant or hydrant in the water 20 distribution block. In this case, a plurality of sensors may be installed by employing a small optical MEMS microphone which enables the sensor capable of catching a vibration sound of water leakage to be manufactured at a cheap price and has a high 25 directivity (which enables a target sound source to be extracted even under noise environment). The water leakage analyzing method of the - 51 embodiment may establish a configuration for remote monitoring for data like an ASP provider as the administrative system 600 as well as build the water distribution management system 606 for managing the 5 water distribution pipe network in a water treatment plant. This configuration may provide information such as HTML created dynamically as a result of activation of the water leakage distribution estimation method on the administrative server (ASP server) 601. 10 Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various 15 modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. In the claims which follow and in the preceding description of the invention, except where the context 20 requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further 25 features in various embodiments of the invention. It is to be understood that, if any prior art publication is referred to herein, such reference does - 51A not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

Claims

1. An apparatus for analyzing water distribution information of each of a plurality of water distribution blocks to be managed, the apparatus being applied to a water 5 distribution management system in which a water distribution pipe network for supplying pure water is divided into the plurality of water distribution blocks, the apparatus comprising: a flow rate measuring means for measuring the flow 10 rate of pure water entering each of the water distribution blocks; a pressure measuring means for measuring the pressure of distributed water of each of the water distribution blocks; 15 a minimum flow rate calculating means for calculating a night minimum flow rate of each of the water distribution blocks based on flow rate data outputted from the flow rate measuring means; a water leakage amount calculating means for 20 calculating the leakage amount of each of the water distribution blocks based on the night minimum flow rate calculated by the minimum flow rate calculating means; and an arithmetic operating means for generating information indicating a relation between the pressure and 25 the leakage amount using the pressure value measured by the pressure measuring means and the leakage amount calculated by the water leakage amount calculating means, wherein - 53 the water leakage amount calculating means assumes that the night minimum flow rate is a sum of the water leakage amount and a night consumption amount so as to estimate the night consumption amount of each of the water 5 distribution blocks to execute an arithmetic operation for estimating the water leakage amount of each of the water distribution blocks based on the night minimum flow rate.

2. The apparatus according to claim 1, wherein the arithmetic operating means establishes an 10 arithmetic expression for calculating the water leakage amount based on a parameter which is a coefficient serving as an index indicating the water leakage characteristic of each of the water distribution blocks and the pressure, and generates information indicating the pressure and the water 15 leakage amount including the parameter calculated by the arithmetic expression.

3. The apparatus according to claim 1, further comprising; a means for executing water leakage diagnostic 20 processing for each of the water distribution blocks based on information outputted from the arithmetic operating means.

4. The apparatus according to claim 1, further comprising; 25 a database means in which history information pieces of pipe renewal constructions for renewing pipes in each of the water distribution blocks are accumulated; and - 54 a pipe renewal construction evaluation means for evaluating the water leakage reduction effect of the pipe renewal construction using information outputted from the arithmetic operating means based on the history information.

5 5. An apparatus for analyzing water distribution information of each of a plurality of water distribution blocks to be managed, the apparatus being applied to a water distribution management system in which a water distribution pipe network for supplying pure water is divided into the 10 plurality of water distribution blocks, the apparatus comprising: a flow rate measuring means for measuring the flow rate of pure water entering each of the water distribution blocks; 15 a pressure measuring means for measuring the pressure of distributed water of each of the water distribution blocks; a minimum flow rate calculating means for calculating a night minimum flow rate of each of the water distribution 20 blocks based on flow rate data outputted from the flow rate measuring means; a water leakage amount calculating means for calculating the leakage amount of each of the water distribution blocks based on the night minimum flow rate 25 calculated by the minimum flow rate calculating means; an arithmetic operating means for generating information indicating a relation between the pressure and - 55 the leakage amount using the pressure value measured by the pressure measuring means and the leakage amount calculated by the water leakage amount calculating means; a Q-H curve arithmetic operating means for calculating 5 Q-H curve information indicating a relation between a pressure value H measured by the pressure measuring means, using a pipe resistance parameter R in each of the water distribution blocks and a flow rate multiplier parameter a, and a flow rate Q measured by the flow rate measuring means; 10 and a rate-of-effectiveness estimating means for estimating the rate of effectiveness from a current amount of entering water in each of the water distribution blocks by superimposing information indicating the relation between 15 the pressure and the water leakage amount generated by the arithmetic operating means on the Q-H curve information.

6. The apparatus according to claim 5, further comprising; an evaluation means for carrying out an evaluation to 20 indicate a water leakage reduction effect of a case where the pressure control is introduced, based on a result of comparing the Q-H curve information with information indicating the relation between the pressure and the water leakage amount, the evaluation means being provided between 25 the water distribution blocks.

7. The apparatus according to claim 1, further comprising; - 56 an updating means which, when the water distribution block is changed, automatically updates a range to be closed along a pipe network leading from a water entering position of the water distribution block as a new water distribution 5 block.

8. An apparatus for diagnosing leakage of water in a water distribution pipe, the apparatus being applied to a water distribution management system in which a water distribution pipe network for supplying pure water is 10 divided into a plurality of water distribution blocks to be managed, the apparatus comprising: a flow rate measuring means for measuring the flow rate of pure water entering each of the water distribution 15 blocks; a minimum flow rate calculating means for calculating a night minimum flow rate of each of the water distribution blocks based on flow rate data outputted from the flow rate measuring means; 20 a pressure measuring means for measuring a pressure of distributed water of each of the water distribution blocks; a water leakage coefficient arithmetic operating means which when the night minimum flow rate calculated by the minimum flow rate calculating means is regarded as a water 25 leakage amount of the water distribution pipe, establishes a relational expression between the pressure value and the water leakage amount based on the leakage amount and the - 57 pressure value measured by the pressure measuring means and generates a leakage coefficient; a pipe information acquiring means which divides the water distribution block into plural areas, and acquires 5 pipe information including at least burying positions of the water distribution pipes for each area; a hydrostatic pressure calculating means for calculating the hydrostatic pressure value of each area using the pressure value and the pipe information; and 10 a water leakage amount calculating means for calculating the water leakage amount of each area using the relational expression between the pressure value and the water leakage amount and the hydrostatic pressure and the water leakage coefficient. 15

9. The apparatus according to claim 8, further comprising; a calculating means for calculating total demand and water leakage amount of the water distribution block based on water consumption information such as a charged water 20 amount, divided water amount, meter non-sensed water amount, regional business consumed water amount, arbitrated reduced water amount; and a means for estimating a night water consumption in a night minimum flow rate time interval based on the night 25 minimum flow rate calculated by the minimum flow rate calculating means, wherein the water leakage coefficient arithmetic operating - 58 means calculates the water leakage coefficient with the night minimum flow rate minus the night water consumption regarded as a water leakage amount.

10. The apparatus according to claim 8, wherein 5 the pipe information acquiring means extracts pipe information which is a cause for a change of the leakage coefficient based on the amount of change of the leakage coefficient from the water leakage coefficient arithmetic operating means and the pipe information. 10

11. The apparatus according to claim 8, wherein the pipe information corresponds to a mesh on a map data as the area and includes information pieces about pipe burying positions, pipe burying period, material, diameter, pipe extension, number of hydrants and the like of each 15 mesh, the information pieces being accumulated in database.

12. The apparatus according to claim 11, further comprising; a water leakage composition ratio arithmetic operating means which allocates a leakage composition ratio to each 20 mesh, with distribution of the pipe extension and the quantity of pipes which are causes extracted pipe information changes, adopted as a water leakage composition ratio, based on the pipe information extracted by the pipe information extracting means and a typical pressure value of 25 each mesh which is a hydrostatic pressure calculated by the hydrostatic pressure calculating means, and calculates the water leakage composition ratio so that a difference between - 59 the leakage amount calculated from the typical pressure value and the water leakage amount of the entire water distribution block to be a minimum.

13. The apparatus according to claim 12, further 5 comprising; a leakage distribution display means which displays an estimated distribution of the water leakage amount calculated based the water leakage composition ratio obtained by the water leakage composition arithmetic 10 operating means, the water leakage coefficient obtained by the water leakage coefficient arithmetic operating means and the typical pressure value of each mesh calculated by the hydrostatic pressure arithmetic operating means on the map data. 15

14. The apparatus according to claim 8, further comprising; a pipe network analyzing means which estimates a leakage amount of each node point based on an effective water pressure of each node point of each water distribution 20 block and the water leakage coefficient introduced from the water leakage amount of the entire water distribution block, and estimates the water leakage amount of the entire block corresponding to a demand pattern, so as to execute pipe network analysis for specifying water consumption at night. 25

15. The apparatus according to claim 14, wherein the pipe network analyzing means executes pipe network analytic calculation when a terminal pressure is controlled - 60 to a particular level in the water distribution block, and evaluates a water leakage amount reduction effect at the time when the terminal pressure control is introduced, based on the total water leakage amount of the water distribution 5 block.

16. The apparatus according to claim 8, wherein the minimum flow rate calculating means includes a night minimum flow rate extracting means which acquires the data about the amount of entering water of the water 10 distribution block by a predetermined data cycle and extracts the data as the night minimum flow rate.

17. The apparatus according to claim 8, further comprising; an automatic meter checking system for automatically 15 collecting data necessary for water leakage diagnosis from the water distribution block using radio communication.

18. A method of water leakage diagnosis for a water distribution pipe, the method being applied to a water distribution management system in which a water distribution 20 pipe network for supplying pure water is divided to a plurality of water distribution blocks to be managed, the method comprising the steps of: measuring a flow rate of pure water entering each of the water distribution blocks; 25 calculating a night minimum flow rate of each of the water distribution blocks based on flow rate data measured by the flow rate measuring step; - 61 measuring a pressure value of distributed water of each of the water distribution blocks; establishing a relational expression between the pressure value and a water leakage amount when the night 5 minimum flow rate calculated by the night minimum flow rate calculating step is regarded as the water leakage amount of the water distribution pipe, based on the water leakage amount and the pressure value measured by the pressure measuring means, so as to generate a leakage coefficient; 10 dividing the water distribution block into plural areas so as to obtain pipe information including at least burying positions of the water distribution pipe for each area; calculating a hydrostatic pressure of each area using 15 the pressure value and the pipe information; and calculating a water leakage amount of each area using a relational expression between the pressure value and the leakage amount and the hydrostatic pressure and the water leakage coefficient. 20

19. A system for distributing water and diagnosing leakage of water, substantially as hereinbefore described with reference to figures 1 to 5, to figure 6, to figures 7 and 8, to figures 9 to 21 or to figure 22 of the accompanying drawings. 25