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I I I I I I I I I I I I I I I I I I I 27 farmers, and also serves as a flood detention dam. The dam is in need of repairs and improvements in order to restore it to the State Engineer's standards. Eastlake Dam No.3 will contain the lOa-year 'storm from its upstream watershed >vi th only a minor discharge flow from the principal spillway. The discharge from the principal spillway combined with local runoff from the 100- year storm result in widespread shallow flooding in the undevel- oped area for over one thousand feet downstream of the dam, as no defined channel exists in this area. The flooded property is primarily stable property interspersed with a few farm houses. Flow from Tributary V combines with flow from Brantner Gulch northeast of Monroe Street. within the banks of the channel. The Tributary III channel is a well defined earth channel with wheat cover, and cattails in the middle reach. The culverts at Holly Street and East l28th Avenue are of insufficient capacity to convey the laO-year flood and these gravel roadways are overtopped during this magnitude storm. The lOa-year flood is contained within the banks of the channel. Because the area adjacent to the channel is undeveloped and is used primarily for agricultural purposes, structural damages are minimal. Brantner Gulch Tributary III and Sub-Tributary III-D (Sheets 16-19) Subtributary III-D originates within the Thornton City Limits just southeast of the Lee Lateral irrigation ditch and flows southeasterly to an intersection with Tributary III. Tributary III originates within the Thornton City Limits south of the origin of Sub-tributary III-D and flows southeasterly to confluence with Brantner Gulch half-way between Holly Street and Quebec Street, in Adams County. Sub-tributary III-D channel is characterized by an open earth channel overgrown with weeds. The channel grade is steep, the channel is narrow and the side slopes are moderately steep. The lOa-year flood is contained Brantner Gulch Tributary IV (Sheets 20, 21) The Tributary IV channel originates in Adams County just north of East 128th Avenue, halfway between Holly Street and Quebec Street. The channel flows proceed southeasterly to an intersection with Brantner Gulch just west of Quebec Street, in Adams County. A small stock pond is located just north of East l28th Avenue and has a slight influence on the floodplain definition. The channel grade is steep. the channel is narrow and the side slopes are moderately steep, weeds and crops cover the channel bottom and side slopes. The culvert at East l28th Avenue is too small for the laO-year flood and the gravel road is overtopped at this point. The lOa-year flood is contained within the banks of the channel for its full length. Land adjacent to the channel is agricultural. No structures are located in the lOa-year floodplain.