Overall Rating Gold
Overall Score 75.90
Liaison Deborah Steinberg
Submission Date Dec. 6, 2021

STARS v2.2

Carnegie Mellon University
OP-21: Water Use

Status Score Responsible Party
Complete 4.00 / 4.00 Martin Altschul
Director of Strategic Facilities Initiatives of FMCS
Facilities Management Services
"---" indicates that no data was submitted for this field

Level of ”Physical Risk Quantity” for the institution’s main campus as indicated by the World Resources Institute Aqueduct Water Risk Atlas:
Low

Total water withdrawal (potable and non-potable combined):
Performance Year Baseline Year
Total water withdrawal 80,666,000 Gallons 123,907,000 Gallons

Potable water use:
Performance Year Baseline Year
Potable water use 80,666,000 Gallons 123,907,000 Gallons

Start and end dates of the performance year and baseline year (or three-year periods):
Start Date End Date
Performance Period July 1, 2020 June 30, 2021
Baseline Period July 1, 2004 June 30, 2005

A brief description of when and why the water use baseline was adopted:

FY 2005 was selected to be consistent with earlier STARS reporting Baseline year. However, the building gross floor area was re-adjusted using performance year methodology. In 2018 CMU revised its approach to calculating square footage. Historically, CMU included in its square footage rented floor area for which we paid utility bills. We also used to calculate square footage using the the area the federal government calls “Net Usable Area." In an effort to standardize our approach to square footage reporting for various campus reports, we now include only the floor area of the buildings we own. We also have shifted to a gross square footage approach, (similar for USGBC and for AASHE).


Figures needed to determine "Weighted Campus Users":
Performance Year Baseline Year
Number of students resident on-site 3,924 3,744
Number of employees resident on-site 0 0
Number of other individuals resident on-site 0 0
Total full-time equivalent student enrollment 12,193.80 8,894
Full-time equivalent of employees 5,192.10 4,032
Full-time equivalent of students enrolled exclusively in distance education 323 106.50
Weighted campus users 13,778.18 10,550.63

Potable water use per weighted campus user:
Performance Year Baseline Year
Potable water use per weighted campus user 5,854.62 Gallons 11,744.04 Gallons

Percentage reduction in potable water use per weighted campus user from baseline:
50.15

Gross floor area of building space:
Performance Year Baseline Year
Gross floor area 6,759,150.76 Gross square feet 5,391,617 Gross square feet

Potable water use per unit of floor area:
Performance Year Baseline Year
Potable water use per unit of floor area 11.93 Gallons per square foot 22.98 Gallons per square foot

Percentage reduction in potable water use per unit of floor area from baseline:
48.07

Area of vegetated grounds:
Performance Year Baseline Year
Vegetated grounds 157.20 Acres 120 Acres

Total water withdrawal per unit of vegetated grounds:
Performance Year Baseline Year
Total water withdrawal per unit of vegetated grounds 513,142.49 Gallons per acre 1,032,558.33 Gallons per acre

Percentage reduction in total water withdrawal per unit of vegetated grounds from baseline:
50.30

A brief description of the institution's water-related behavior change initiatives:

To date, the university has focused on widespread installation of presence-sensing devices, flow controllers, and low-flow fixtures and fittings within buildings to reduce water consumption. As an integrated environmental strategy, we have also replaced many standard water fountains with water-refill stations in order to reduce the impact of bottled water use. We have recently updated controls on irrigations systems for our main quadrangle, resulting in irrigation consumption reduction by 37%.


A brief description of the institution's water recovery and reuse initiatives:

In 2016, CMU installed 275,000 gallons of rainwater collection and storage capacity below grade in the center of campus. Downspouts from surrounding buildings (Baker, Porter & Doherty Halls) feed the storage tanks. Collected water can be routed to the chiller plant for cooling tower make-up and can also serve our limited irrigation needs.

Our Gates Hillman Computer Science Complex has a 10,000-gallon rainwater collection tank within the building. That water is used for flushing building toilets. Vegetated swales and tree plantings on hillside where that building is situated slow water flow.

The Collaborative Innovation Center (CIC) has a 6,000-gallon rainwater storage tank to supply toilets & irrigation.

Purnell Center for the Arts has a 10,000-gallon underground baffled stormwater cistern to slow water flow.

The Tepper Quad collects rain water from the building roof and grounds to a 150,000 gallon cistern located in the building for use as the water for toilet flushing.

In addition, Carnegie Mellon has over a dozen buildings with green roofs, (living or vegetated roofs), and several rain gardens. Because of abundant rainfall and old stormwater infrastructure in Pittsburgh, campus design and facilities personnel make considerable effort to preserve permeable area despite the increase in new buildings on campus.


A brief description of the institution's initiatives to replace plumbing fixtures, fittings, appliances, equipment, and systems with water-efficient alternatives:

See above. Low and ultra-low urinals are used for all new construction and renovations. Other high efficiency fixtures such as touchless faucets are also used.


Website URL where information about the institution’s water conservation and efficiency efforts is available:
Additional documentation to support the submission:
---

Data source(s) and notes about the submission:

Baseline year building gross floor area was re-adjusted using performance year methodology.

Great efforts have been taken to reduce campus energy uses since our baseline year of 2005. Campus-wide initiatives described above have allowed us to greatly reduce potable energy use.


Baseline year building gross floor area was re-adjusted using performance year methodology.

Great efforts have been taken to reduce campus energy uses since our baseline year of 2005. Campus-wide initiatives described above have allowed us to greatly reduce potable energy use.

The information presented here is self-reported. While AASHE staff review portions of all STARS reports and institutions are welcome to seek additional forms of review, the data in STARS reports are not verified by AASHE. If you believe any of this information is erroneous or inconsistent with credit criteria, please review the process for inquiring about the information reported by an institution or simply email your inquiry to stars@aashe.org.