Historic Resource Evaluation Project - Tuolumne Utilities District

For Criterion C, according to JRP and Caltrans:
Water conveyance systems have been found eligible for the NRHP under
Criterion C for their engineering or design values. Examples of different
types, periods, or methods of construction; … and properties which
together constitute a historic district may be eligible under Criterion C …
or be the best or good examples of a type of property. The earliest, best
preserved, largest, or sole surviving examples of particular types of water
conveyance systems or a property that introduced a design innovation may
be eligible as examples of evolutionary trends in engineering (JRP and
Caltrans 2000:93-94).
The evaluation procedures go on to state:
Water conveyance systems that appear to meet the National Register
criteria must also retain integrity, which is the ability of a property to
convey its significance…. To address integrity, the appearance of the
water system and its design during its period of significance must be
known and the following questions should be asked: Does the system
follow the alignment of its period of significance? Have the significant
elements of design, materials, and workmanship been retained? Does the
setting still evoke the important qualities of the water system? And does
the property retain the feeling and associations needed to convey its
significance?...
As with other types of historic properties, the fundamental test of the
integrity of a water conveyance system consists of the relationship
between its current appearance and its appearance during the period of its
significance. Integrity will not be lost as the result of modifications that
were undertaken during the system’s period of significance, and
modifications made within that time may actually contribute to the
importance of the property. Subsequent repairs or modifications may have
greater effects on the system’s integrity than abandonment and
deterioration of the system… (JRP and Caltrans 2000:95).
In California, eligible ditches range from small stream diversions for ranches and farms,
to abandoned mining enterprises, to enormous governmental undertakings. The complex
of ditches, canals, tunnels, and weirs that organize the Santa Ana River waters near
Redlands were determined eligible for National Register listing as part of two district
nominations. One included more than 15 irrigation canals and another added powergeneration
systems to an existing nomination for the powerhouses (Hornbeck and Botts
1988). In 1992, Caltrans recorded the 340-mile long Los Angeles Aqueduct as sites CA-
INY-459H, CA-MNO-2753H, and CA-LAN-2105H (trinomials change with county)
(Costello and Marvin 1992).
Foothill Resources, Ltd. 4.2 TUD Ditch Sustainability Project
Francis Heritage, LLC
Historic Resource Evaluation Report