Navajo-Gallup Water Supply 

Project Newsletter 3rd Quarter, April 2023

Construction Continues at 

Sanostee and Hogback Chapters

By Ryan Royer, Civil Engineer, Bureau of Reclamation

Construction continues to progress on the San Juan Lateral on the NavajoGallup Water Supply Project with new projects planned by Reclamation, 

the Navajo Nation, Indian Health Service, and the city of Gallup. 

Currently, Reclamation’s construction contractor, Archer Western, has two 

pumping plants located in the Twin Lakes and Sheep Springs chapters 

under construction. Additionally, there is a stretch of 30- and 24-inch pipe 

being installed from Yah-tah-hey Junction by Reclamation’s contractor, SJL 

Construction, west through the Rock Springs and Tsayatoh chapters to the 

Arizona/New Mexico state line. 

Beginning this spring, even more of the project will move into the 

construction phase, including two more pumping plants: the Tsé Da’azkání 

Pumping Plant (2) and Tó Ałts’íísí Pumping Plant (3); as well as roughly 18 

miles of 42-inch pipe for the Block 4A-4B pipeline. Much of this 

construction will take place in the Tse anaozt'ii (Sanostee) Chapter, except 

for Reach 4A construction in the Tse Dáá K’áán (Hogback) Chapter. 

One of the pumping plants will be easy to see, as it is located along 

highway 491 around ISR 5016. There, the pumping plant (Tó Ałts’íísí ) 

will connect to pipe already in the ground on the south end, which is Reach 

4C. Inside of the pumping plant, a bank of four, 1,000 horsepower motors 

will be installed to move the water south when construction of the entire 

project is complete. The Reach 4B pipeline will supply water to the Tó 

Ałts’íísí pumping plant through an 11-mile long, 42-inch diameter pipe. 

There, an additional pumping plant (Tsé Da’azkání) will be constructed. 

This pumping plant will have four smaller, 600 horsepower motors to 

assist with moving the water to communities in the south. From this 

pumping plant continuing farther north still, the Reach 4A pipeline, which 

is 7 miles of 42-inch diameter pipe, will be laid into the earth. 

The location where Reach 4A begins is of particular importance, as it will connect directly to the San Juan Lateral Water Treatment 

Plant which will provide a clean, reliable source of water from the San Juan River to the Diné people for generations to come. Once 

Block 4A-4B is completed in 2025, continuous pipe will stretch from Highway N36 in the north, all the way to the south of Gallup

for a total distance of about 100 miles. 

Map of the upcoming construction area of the pumping 

plants and waterline located within the Sanostee and Hogback 

Chapters

Faces of NGWSP

Marc A. DePauli is a licensed civil 

engineer and land surveyor from Gallup, 

New Mexico. Marc attended Gallup High 

School and received a Bachelor’s in Civil 

Engineering from the University of 

Arizona and has always worked in the 

Colorado River Basin. Marc is the owner 

of DePauli Engineering & Surveying, 

LLC, and is responsible for the oversight 

of all the planning, design, surveying, and 

construction management of the firm, 

which is contracted with the city of 

Gallup. The firm provides engineering and 

construction management services and has 

represented the city’s interests on the 

NGWSP since 2000. Marc’s long-time 

resident knowledge and understanding of 

the project has been immensely helpful to 

help us meet the demands for the future 

water supply of the city of Gallup and 

surrounding areas because of the rapidly 

declining groundwater levels. 

If you would like to learn more, visit or website at:

https://www.usbr.gov/uc/progact/navajo-gallup/.
Hilda Castillo-Smith Named Reclamation’s 2023 Regional Engineer of the Year

This year, the honor of the Regional Offices’ Engineer of the Year went to the Upper Colorado 

Region’s Hilda Castillo-Smith from the Four Corners Construction Office for her impressive 

work on the important Navajo-Gallup Water Supply Project. 

Working as a civil engineer for Reclamation, Hilda employs a unique and diverse skillset to 

design, develop, implement, and manage construction of several of the nation’s most 

challenging and critically needed engineering projects. She serves as a lead resident engineer 

responsible for delivering reliable drinking water to the Navajo Nation.

“She’s an engineer who performs at an exceptional level, including on some aspects outside of 

her typical engineering duties such as public outreach,” said her supervisor, Field Engineering 

Division Manager Emma Manzanares. 

Castillo-Smith manages construction on contracts worth a total value of $175 million. In the 

past three years, she has served as the resident engineer on the high-profile projects critical to fulfilling our nation’s treaty 

obligations to the Navajo Nation. 

“We’re grateful for Hilda’s exceptional professionalism and going the extra mile in supporting Reclamation’s mission,” said Upper 

Colorado Basin Regional Director Wayne Pullan. “Her considerable engineering contributions have enhanced Tribal relationships

and improved water supplies throughout the Four Corners region.” 

Water Source for the Navajo-Gallup Water Supply Project

By Dex Lewis, Civil Engineer, Bureau of Reclamation

Did you know that the Navajo-Gallup Water Supply raw water comes from one main source, the San Juan River and its tributaries? 

The San Juan River is the inflow and outflow of the Navajo Dam, which is the upstream impoundment of storage water for the 

river. The NGWSP consists of two laterals, the Cutter Lateral and the San Juan Lateral, which service potable water for the eastern 

and western Navajo communities in New Mexico, respectively. So how do these laterals get their water?

CUTTER RESERVOIR AND LATERAL

The Cutter Dam was constructed under the Navajo Indian Irrigation Project (NIIP) and is operated and maintained by the Navajo

Agricultural Products Industry through a contract with the Bureau of Indian Affairs as the irrigation source water for the NIIP 

farm system. Its source water is Navajo Dam via a series of canals and tunnels. Cutter Reservoir was chosen as the source water for 

the Cutter Lateral for multiple reasons, including its location, storage capacity and ability to settle sediments from the water. Cutter 

Reservoir is approximately 64 acres in surface area and offers approximately 900 acre-feet of active storage. Downstream of the 

reservoir, two pumping plants lift the raw water to the Cutter Lateral Water Treatment Plant through approximately 20 miles of 20-

inch and 24-inch pipeline. The CLWTP currently has a maximum peak treatment flow of 3.5 million gallons per day with the ability

to be expanded to produce 5.4 MGD at full buildout and has been in 

operation since October 2020. 

SAN JUAN LATERAL AND SAN JUAN GENERATING 

STATION RESERVOIR

The San Juan Lateral source water will be the San Juan River via the San 

Juan Generating Station Intake Pumping Plant that diverts and pumps 

water to the SJGS Reservoir. The Bureau of Reclamation is acquiring the 

SJGS Reservoir and river intake pumping plant for use on the San Juan 

Lateral. The reservoir has a surface area of approximately 130 acres and 

2,740 acre-feet of active storage. As of March 2023, Reclamation is in the 

initial design phase of a new Pumping Plant #1 located near the river. 

This pumping plant will pump raw water from the SJGS reservoir to the 

San Juan Lateral Water Treatment Plant, which is located approximately 

10 miles southwest. The treatment plant will be designed in phases to 

meet startup and initial demand flows and have the capability to expand 

to meet future 40-year population demand growths: It will produce a 

peak supply of 18.8 MGD to meet initial demands with the deferred 

expansion to produce 37.6 MGD at full build-out. Reclamation is 

currently soliciting a design-build contract anticipated to be awarded in 

the spring of 2024 with a completion date of 2029, with initial deliveries 

of clean, reliable and more sustainable drinking water to Navajo 

communities and the city of Gallup in 2028. 

Navajo-Gallup Water Supply Project water source for the 

Cutter Lateral and San Juan Lateral 

If you would like to learn more, visit or website at:

https://www.usbr.gov/uc/progact/navajo-gallup/.