SURFACE-WATER FIELD TECHNIQUES

---

Merced River at Happy Isles Bridge, near Yosemite, California - n = 0.065

---

Site Description

 

Station name	Merced River at Happy Isles Bridge, near Yosemite, California
Station number	11-2645
Gage location	Lat 37°43'54'', long 119°33'28'', on right bank 10 ft downstream from Illilouette Creek, and 2 miles southeast of Yosemite National Park Headquarters, Mariposa County. Section 1 is about 1,000 ft downstream from gage.
Drainage area	181 sq mi.
Date of flood	May 17, 1950
Gage height	6.06 ft at gage; 97.40 ft (different datum) at section 1
Peak discharge	1,950 cfs
Computed roughness coefficient	Manning n = 0.065
Description of channel	Fairly straight channel is composed of boulders with trees along top of banks; d50 = 253 mm, d84 = 550 mm. Banks are composed of boulders and have trees and brush.

Introduction Page || Site Description || Reach Properties
Plan Sketch and Cross Sections || Site Photos

---

Reach Properties

 

Section	Area (sq ft)	Top Width (ft.)	Mean depth (ft)	Hydraulic radius (ft)	Mean velocity (ft per sec)	Lenght (ft) between sections	Fall (ft) between sections
1	308	78	4.0	3.90	6.33	.......	.....
2	263	64	4.1	3.98	7.41	200	3.40
3	309	63	4.9	4.68	6.31	40	0.50
4	327	78	4.2	4.09	5.96	180	1.55

Introduction Page || Site Description || Reach Properties
Plan Sketch and Cross Sections || Site Photos

---

Plan Sketch and Cross Sections

Introduction Page|| Site Description || Reach Properties
Plan Sketch and Cross Sections || Site Photos

---

Site Photos