+
+
+
+ EPANET
+Industry-Standard Software for Modeling Hydraulic and Water Quality Behavior of Water Distribution Systems
+ +
+ 
+
+
+ Complete guide to using EPANET and its Programmer's Toolkit API
+EN_createproject, EN_deleteproject, EN_open, EN_saveinpfile, EN_close
+EN_solveH, EN_openH, EN_initH, EN_runH, EN_nextH, EN_closeH
+EN_solveQ, EN_openQ, EN_initQ, EN_runQ, EN_nextQ, EN_closeQ
+EN_report, EN_setreport, EN_writeline, EN_geterror
+EN_getoption, EN_setoption, EN_gettimeparam, EN_settimeparam
+EN_addnode, EN_addlink, EN_getnodevalue, EN_setnodevalue
+Learn how to use EPANET with practical code examples and network models
+Run a complete hydraulic simulation with EPANET Toolkit:
+#include
+#include
+
+int main() {
+ EN_Project ph;
+ int errcode;
+
+ // Create a new EPANET project
+ errcode = EN_createproject(&ph);
+ if (errcode != 0) {
+ printf("Error creating project: %d\n", errcode);
+ return 1;
+ }
+
+ // Open an existing network file
+ errcode = EN_open(ph, "Net1.inp", "Net1.rpt", "Net1.out");
+ if (errcode != 0) {
+ printf("Error opening file: %d\n", errcode);
+ EN_deleteproject(ph);
+ return 1;
+ }
+
+ // Run hydraulic analysis
+ errcode = EN_solveH(ph);
+ if (errcode != 0) {
+ printf("Error in hydraulic analysis: %d\n", errcode);
+ }
+
+ // Generate report
+ EN_report(ph);
+
+ // Clean up
+ EN_deleteproject(ph);
+ return 0;
+} Run a water quality simulation with chlorine decay analysis:
+#include
+
+int main() {
+ EN_Project ph;
+
+ // Create and open project
+ EN_createproject(&ph);
+ EN_open(ph, "Net1.inp", "quality.rpt", "quality.out");
+
+ // Run hydraulic analysis first
+ EN_solveH(ph);
+
+ // Run water quality analysis
+ EN_solveQ(ph);
+
+ // Generate report
+ EN_report(ph);
+
+ // Clean up
+ EN_deleteproject(ph);
+ return 0;
+} Access intermediate hydraulic results during simulation:
+#include
+
+int main() {
+ EN_Project ph;
+ long t, tstep;
+ double pressure, flow;
+ int nodeIndex, linkIndex;
+
+ // Create and open project
+ EN_createproject(&ph);
+ EN_open(ph, "Net1.inp", "Net1.rpt", "");
+
+ // Open hydraulic solver
+ EN_openH(ph);
+ EN_initH(ph, EN_SAVE); // Save intermediate results
+
+ // Run extended period simulation
+ do {
+ EN_runH(ph, &t);
+
+ // Get node pressure at current time
+ nodeIndex = 1; // Node 1
+ EN_getnodevalue(ph, nodeIndex, EN_PRESSURE, &pressure);
+
+ // Get link flow at current time
+ linkIndex = 1; // Link 1
+ EN_getlinkvalue(ph, linkIndex, EN_FLOW, &flow);
+
+ printf("Time: %ld, Pressure: %.2f, Flow: %.2f\n", t, pressure, flow);
+
+ EN_nextH(ph, &tstep);
+ } while (tstep > 0);
+
+ EN_closeH(ph);
+ EN_deleteproject(ph);
+ return 0;
+} Modify network elements programmatically:
+#include
+
+int main() {
+ EN_Project ph;
+ int nodeIndex;
+ double newDemand;
+
+ // Create and open project
+ EN_createproject(&ph);
+ EN_open(ph, "Net1.inp", "Net1.rpt", "");
+
+ // Get node index by ID
+ EN_getnodeindex(ph, "11", &nodeIndex);
+
+ // Modify node demand
+ newDemand = 200.0; // GPM
+ EN_setnodevalue(ph, nodeIndex, EN_BASEDEMAND, newDemand);
+
+ // Save modified network
+ EN_saveinpfile(ph, "modified_network.inp");
+
+ // Run analysis on modified network
+ EN_solveH(ph);
+ EN_solveQ(ph);
+ EN_report(ph);
+
+ EN_deleteproject(ph);
+ return 0;
+} Create a water network programmatically without an input file:
+#include
+
+int main() {
+ EN_Project ph;
+ int j1, j2, p1, t1, r1;
+
+ // Create a new project
+ EN_createproject(&ph);
+
+ // Initialize project with units and headloss formula
+ EN_init(ph, "report.rpt", "output.out",
+ EN_GPM, EN_HW); // GPM, Hazen-Williams
+
+ // Add nodes
+ EN_addnode(ph, "J1", EN_JUNCTION, &j1);
+ EN_addnode(ph, "J2", EN_JUNCTION, &j2);
+ EN_addnode(ph, "Tank1", EN_TANK, &t1);
+ EN_addnode(ph, "Reservoir1", EN_RESERVOIR, &r1);
+
+ // Set node properties
+ EN_setjuncdata(ph, j1, 100.0, 100.0, ""); // Elev, Demand
+ EN_setjuncdata(ph, j2, 95.0, 100.0, "");
+
+ // Add links (pipes)
+ EN_addlink(ph, "P1", EN_PIPE, "J1", "J2", &p1);
+
+ // Set link properties
+ EN_setlinkvalue(ph, p1, EN_LENGTH, 1000.0);
+ EN_setlinkvalue(ph, p1, EN_DIAMETER, 12.0);
+ EN_setlinkvalue(ph, p1, EN_ROUGHNESS, 0.1);
+
+ // Run analysis
+ EN_solveH(ph);
+ EN_report(ph);
+
+ EN_deleteproject(ph);
+ return 0;
+} Pre-built example networks are available in the example-networks directory:
These networks demonstrate various features of EPANET including:
+Industry-Standard Software for Modeling Hydraulic and Water Quality Behavior of Water Distribution Systems
+ +
+ Model steady-state and extended period simulations of water flow, pressure, and tank levels.
+Analyze the fate and transport of chemical constituents and trace the source of contamination.
+Programmatic access to EPANET's engine for custom applications in C/C++.
+Model complex water distribution networks with pumps, valves, tanks, and pipes.
+Evaluate system performance under various operating conditions and demand patterns.
+Community-driven development with contributions from researchers and practitioners worldwide.
+EPANET is an industry-standard program for modeling the hydraulic and water quality behavior of water distribution system pipe networks. Originally developed by the U.S. Environmental Protection Agency (USEPA), it is now maintained by the Open Water Analytics (OWA) community.
+The EPANET Programmer's Toolkit is a library of functions (or API) written in C that allows programmers to customize the use of EPANET's solution engine for their own applications.
+ Learn More +// C Example - Simple EPANET Analysis
+#include
+
+int main() {
+ EN_Project ph;
+ EN_createproject(&ph);
+ EN_open(ph, "network.inp", "network.rpt", "network.out");
+ EN_solveH(ph); // Run hydraulic analysis
+ EN_solveQ(ph); // Run water quality analysis
+ EN_report(ph); // Generate report
+ EN_deleteproject(ph);
+ return 0;
+} Use the Toolkit API to integrate EPANET into your applications. See the Documentation for more details.
+Contribute to EPANET development, report issues, or get help from the community.
+ +