cocog13.02 Boyd Freeman Headgate.docx 1 of 2 Anderson Consulting Engineers, Inc.

View Downstream at Headgate Structure

Erosion at Headgate Structure

Boyd and Freeman Headgate Rehabilitation and Return Structure Project

Greeley, Colorado

Client: Mr. Phill Carter

The Boyd Irrigation Company

1100 10th Street, 3rd Floor

Greeley, Colorado 80631

(970) 350-9826

The Cache La Poudre River (Poudre) flooding in May and June 2010 directed overbank flows

into the Boyd and Freeman Ditch (BFD) that resulted in considerable damage to the ditch and

diversion facilities. The BFD headgate and check dam are located on the main channel of the

Poudre approximately 8,500 feet west of 35th

Avenue and 500 feet north of F Street.

Approximately 200 feet west of the diversion dam/headgate structure there is a high flow bypass

channel with a second check dam. The BFD headgate and check dam, both concrete, have long

been in overall poor condition. Water

rights for the BFD were first

appropriated on March 15, 1862, which

gives an indication of the potential age

of the existing headgate facility.

During the spring of 2010 flooding

event on the Poudre, debris in the

bypass channel may have exacerbated

flooding conditions at the headgate.

The headgate diversion dam was

severely damaged and the headgate

structure concrete walls experienced

erosion damage when the 2010 flood

flows overtopped the structure. A head

differential flow measurement structure

is presently located at the BFD

headgate slidegates. Due to the limited

functionality of the existing slide gates,

and high tailwater conditions in ditch,

the measurement structure has not

gained acceptance by the Colorado

Division of Water Resources (CDWR).

The objective of this project was to

develop alternative concepts for

replacing/repairing the headgate and check

dam with the addition of an integral

measured return flow structure, develop

alternatives for replacing the measurement

device with one acceptable to the CDWR,

assist the ditch company with selecting an

alternatives, and complete final designs

based the selected alternatives. This

project consisted of the following:

cocog13.02 Boyd Freeman Headgate.docx 2 of 2 Anderson Consulting Engineers, Inc.

Debris at Bypass Channel

• Formulation and hydraulic evaluation of conceptual alternatives to meet the project objective;

• Formulation of cost estimates for conceptual alternatives;

• Hydraulic analysis and final design of concrete check dam and headgate, incorporating floating

debris and sediment handling systems;

• Hydraulic analysis and final design of meter vault for 48-inch diameter electromagnetic flow

meter and associated valving;

• Hydraulic analysis and final design

of a 100-foot long, 48-inch diameter

PVC pipe conveyance to direct flow

through the 48-inch meter;

• Hydraulic analysis and final design

of meter vault for 18-inch diameter

electromagnetic flow meter and

associated valving;

• Hydraulic analysis and final design

of a 35-foot long, 18-inch diameter

PVC pipe conveyance to direct flow through the 18-inch meter;

• Removal of debris to enhance capacity

of bypass channel;

• Project area grading and reclamation;

• Preparation of final design drawings

and contract documents; and

• Project observation during the approximately 2-month construction time period.

Headgate Structure Grading Plan