WSP06617

• File Number: 8200.750
• Description: San Juan River General
• State: CO
• Basin: San Juan/Dolores
• Water Division: 7
• Date: 10/15/1956
• Author: BOR
• Title: O Neal Park Project - Colorado - Reconnaissance Report - October 1956
• Water Supply Pro - Doc Type: Report/Study

OlJ3325

CHAPTER III

PO'lENTIAL IRRIGATION DEVELOPMENT

.

'lhe canal and lateral aligmnent Ellld sections were obtaiIled from
aerial photos with the aid of' a stereoscope. Typical sections of unlined
canal, chutes, checks, turnouts, and div:l.sion boxes were designed to fit
the terrain observed from the aerial photos and from rough reconnaissance
field inspections.

Sublaterals and DraiIls

Several miles of laterals of relatively small capacities would be
required to serve the project area. III view of the relation of the lands
to the outlet canals, main laterals, and type of terrain, the average cost
of the laterals was est:lmated at $45 per irrigable acre. 'lhis lateral
cost was estimated from general data and from costs per acre for serving
comparable lands on other projects. The laterals were not specifically
located nor designed.

A limited drainage system consisting pr:!mar:l.ly of surface drains
would be required for sane of the project lands, particularly those
located on the lower slopes and bottoms of small drainages which are
composed of heavy soils. Drainage costs averaging $15 per irrigable
acre for the entire project were estimated from general data on costs per
acre for draining similar land on other projects. Drains required for
. the project were not specifically located nor designed.

Estimated Costs

Reconnaissance estimates were made of the construction costs of
O'Neal Park project features on the basis of October 1955 prices.
Allowances were made in the estimates for contingencies of 25 percent
and engineering and ovemead of 30 percent. Costs have been included
for future investigatioos.

The cost of Perry Draw Dam wai ,obtained :from Drawing Nos. 130-D-358,
359, and 361 entitled "Earth Dams"J, included in the Bureau's Project
Planning Estimating Data. Appropriate indexes were applied to the esti-
mate to reflect October 1955 prices.

'lhe costs of Perry Draw InJ.et Canal and wasteway were based on the
alignment and sections obtained from aerial photos. Typical sections
were designed to fit the required capacity and 8 unit cost per foot was
estimated for each type of section. 'lhese unit costs were then applied
to the required length of the various sections.

'lhe cost of the diversion dam on the Piedra. River was es:J;:t.mated
using curves on Drawing 103-D-364, entitled "Diversion IBms" Y. Unit

.

1/ Figures 3, 4, and 6, Par. 1.4, Specialist Supplement No. 1 to
Part 8 of Volume X of' the Reclamation Manual.
y Figt.lre 12, Par. l.ll, Specialist Supplem~nt No. 1 to Part 8
of Volume X of the Reclamation Manual.

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