Annual rainfall data for station A as well as the annual rainfall values for a group of three neighboring stations located in a meteorologically homogeneous region are given below. Test the consistency of the annual rainfall data of station A and correct the record if there is any discrepancy. Estimate the mean annual precipitation at station A. Year Station A Station B Station C Station D 1990 140.15 78.4 77.2 79.7 1991 125.2 67.9 66.5 69.4 1992 123 60 61.3 65.3 1993 116.9 62.3 68.1 71.7 1994 155.1 81.8 80.1 83 1995 168.1 87.3 85.6 82.7 1996 88.6 89.9 90.1 89.4 1997 93.7 94.7 93.7 91.5 1998 93.5 92.8 91.5 92.4 1999 90.2 89.9 90.3 90.1 2000 83.5 84.9 83.6 82.3 2001 82.4 87.1 83.4 80.7

6- Maximum annual rainfall depth data are fitted with a distribution that is positively skewed (i.e., it has a longer tail to the right). If the mean value for the distribution is 4.22 in, then the rainfall depth with return period 2 years will be (use the next page table): (5 p) (A) Strictly less than 4.22 in (B) Equal to 4.22 in (C) Strictly larger than 4.22 in (D) None of the above

Hydrology Problem: Develop a synthetic rainfall hyetograph for a 6 hr, 10-year rainfall event for Houston, TX using a time step of 30 min. Arrange to be an early peaking event.

Determine average rainfall using Arithmetic mean method

Using a rainfall of 386 mm for rain gauge Station D, determine the average depth of rainfall that fell for the watershed using the arithmetic average, and Thiessen polygon method. The areas for the Thiessen polygon method are given in the table above for each station. Determine the average depth of rainfall for a watershed using the isohyetal method given the data below. Isohyet (mm) Area Associated (km²) 30 - 40 20 20 - 30 45 10 - 20 35 under 10