COMPARISON OF SNYDER SYNTHETIC UNIT HYDROGRAPH WITH MEASURED UNIT HYDROGRAPH ON BIONGA KAYUBULAN
Barry Labdul;AryatiAlitu

Gorontalo State University
Jl. Jend. Sudirman No.6 Gorontalo
Email : barrylabdul39[at]gmail.com , aryati_alitu[at]ung.ac.id

Abstract

Generally, syntchetic unit hydrograph had to be developed just like kind of synder that found accord empire scientific in United States. Determination of their parameters have been presented by various criteria, but so far the results are still relatively deviate for watershed-watersheds in Indonesia. The study was conducted to Bionga Kayubulan sub watershed that have properties and characteristics that need to be conducted regarding irregularities by comparing models HSS Synder with unit hydrograph observations on sub watershed.
Hydrograph water level readings AWLR derived from a flood hydrograph, using the are discharge. to separate the base flow with run off straight line method is used to produce direct run off hydrograph. From the data obtained ARR hourly rainfall records were the analyzed, using the equation effectve rainfall of index Φ. Direct run off hydrograph and rainfall effectively revealed to be the observation unit hydrograph using collins method. Based on topographic maps obtained wathershed physical factors were then used to analyze HSS snyder. Further comparison of the HSS Snyder constant adjusements made using software Microsoft Excel-Solver.
Observation unit hydrograph Bionga Kayubulan sub watershed has a peak time (Tp) of 4.5 hours with a peak discharge (Qp) of 2.81 m3/sec while snyder HSS obtained from the analysis of Tp and Qp of 5.15 hours of 0.33 m3 / dt. The test results showed that the predicted ratio Snyder HSS HSS calibration better than Snyder before calibration. CE preadjusted value is 0.11 and as adjusted to 0.93. value of EV adjusted is 65.20% before and after adjusment to 2.70%. EQP value addition, AETR values and values after adjusting widened AETp 0 hours.

Keywords: HSS Snyder, Calibration, Peak Discharge

Topic: Civil Engineering