Hensel Phelps – Mule Creek State Infill Complex

California has long history of prison overcrowding, but the issue came to a head in 2011 when the U.S. Supreme Court affirmed a lower court order for the state to reduce its then 156,000-person prison population – twice the designed capacity – to 137.5 percent of capacity.

To accommodate that order, the California Department of Corrections and Rehabilitation (CDCR) was forced to release thousands of inmates, but also began considering new facilities to relieve overcrowding. In 2012, the California legislature authorized CDCR to construct three new housing unit facilities at existing prison sites, including the Mule Creek State Prison, a complex that sits on 866 acres of mostly undeveloped land in the city of Ione, about 33 miles south of downtown Sacramento. The following year, the CDCR issued a site-specific evaluation report that recommended the construction of a new 1,584-bed jail on the Mule Creek property.

Work on the Mule Creek Infill Complex began in spring 2014 and is utilizing the design/build process. Construction company Hensel Phelps was awarded a $330 million contact to build the facility in March 2014; however, the total cost of the project is expected to approach $488 million, according to the California State Public Works Board. The new prison is being funded through a bond issuance. Occupancy is expected to begin in March 2016 with the total project being completed by May 2016.

Hensel Phelps specializes in seeing projects through from design to construction and facility management. The company has extensive experience in a variety of fields, including aviation, commercial, education, renewable energy facilities and education buildings. No matter what the type of job, Hensel Phelps says it views each project as a landmark in the making.

Construction is occurring alongside the active Mule Creek State Prison, which houses Level I, III and IV inmate classifications. The new facility will contain Level II inmates. The original prison opened in June 1987 and provides vocational, academic and industrial programs for inmates on site. Like other California jails, Mule Creek State Prison experienced severe overcrowding for many years. 

The problem peaked in 2006 when the prison held 3,965 inmates despite a design capacity of 1,700. That number has gradually decreased to 2,865 inmates in fiscal year 2012-13, according to the prison. CDCR’s long-term plan for the original prison calls for further decreasing the inmate population to 2,400 people, according to the 2013 site evaluation report.

Building a Modern Prison

Although the new Mule Creek Infill Complex will have some autonomy in terms of inmate housing, programing and healthcare services, it will operate under the authority of the existing prison and will depend on the original facility for several support functions. The infill project area comprises 24 buildings on 76 acres, according to the California State Public Works Board. Most of the site is previously undeveloped land that was used as spray fields for disinfected wastewater generated at Mule Creek State Prison and treated onsite before being pumped into the nearby Mule Creek Reservoir.

To prepare the land, Hensel Phelps’ crews had to cut about 40 feet into a mountain and excavate about 1 million cubic yards of dirt. The site requires the installation of all-new utilities, a vehicle patrol road and more than one mile of lethal electrified fencing. There will be six single-story housing units, each about 40,000 square feet in size with a mezzanine and space for 264 inmates. The new jail will have 90,000 square feet of space for programming, recreation and support services.

To deliver the project, Hensel Phelps is working with electrical contractor Bergelectric. The companies have collaborated on past jail projects such as the Coalinga State Hospital Secure Treatment Facility, a maximum-security psychiatric hospital in California that was completed in 2008.

Once completed, the Mule Creek Infill Complex will have flexible housing for inmates with disabilities and intermediate medical or mental health treatment needs while complying with the court order to provide adequate inmate healthcare and reduce overcrowding. Operating the complex will require 377 new employees, more than half of whom would be correctional officers and the remainder medical and mental health personnel, vocational and educational staff, facility maintenance personnel and administrative support staff, according to the CDCR site evaluation report.

Although much of the work is focusing on the Mule Creek Infill Complex, the original Mule Creek State Prison will also see some renovations because the existing prison will provide many of the new facility’s support functions, according to the California State Public Works Board. The Mule Creek State Prison’s central kitchen will be renovated, the warehouse will be overhauled and expanded, a new radio tower and communications equipment vault will be built and parking improvements will be made.

Construction Goals

Like every state, inmate behavior in California is held to a high standard, but the CDCR does not operate on the honor system. The jail must be built strong and safe to ensure prisoners remain inside to complete their sentence. 

The construction of the Mule Creek Infill Complex reflects the need for thick, guardable buildings. The foundations for each of the new buildings are slab-on-grade construction with concrete or concrete masonry exterior walls, according to the California State Public Works Board. The interior construction calls for painted concrete and masonry walls or gypsum board sheathing over light gauge steel stud framing. 

The buildings themselves are designed to be environmentally sustainable, with the goal of achieving a LEED Silver rating from the U.S. Green Building Council once the project is completed. 

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