DDW-2024-004233

DDW-Eng-0015 Page 1 of 1 6/5/2020
Minimum Separation Standards for Water and Sewer Lines – Plan Review of 6’
Horizontal Separation and Exception Requests

This list is for Division of Drinking Water internal use to review acceptable design and exception
requests related to the minimum separation requirements in R309-550-7. Water systems should identify
the following information, which will be used to assess the risk to public health and the degree of
protection need ed to justify approving the design or granting the exception.

☐ 1. Water System N ame: Metropolitan Water District Water System N umber: UTAH 18016
☐ 2. N ame, contact information, and job title of the person making the exception request or proposing
the design [This person must be a water system’s representative or its agent.]
Name: Ammon Allen Title: MWDSLS Engineering Manager
Phone Number: [phone] Email: [e-mail]
☐ 3. Reason for not meeting the minimum separation standards (e.g., constraint due to road or
existing utilities, etc.)
This request is for two exception requests for areas not meeting the minimum separation
standards in this Project. The answers (to all questions) will be organized by exemption request,
identified as exemption request 1 and 2.
1) The proposed new waterline requires this existing sanitary sewer to be vertically relocated.
The existing sanitary sewer alignment does not have the 6 -ft horizontal separation from the
nearby existing water line. Constraint due to other utilities.
2) The proposed new waterline is not able to meet the minimum separation standards, of 6-ft
from a nearby existing sanitary sewer, due to constraints of existing utilities and available
space in the corridor along Fort Union Boulevard.
☐ 4. Location(s) where the water line and sewer line cross or do not meet the minimum
horizontal/vertical separation standards (e.g., station information, street or intersection names,
address, building name, etc.)
1) Drawing SLAR -P-14, at STATION 127+50, intersection of Antler Way and Nutree Drive.
2) Drawing CC -1-P-22, from (approximately) STATION 215+95 to 216+75, Fort Union
Boulevard.
☐ 5. Description of the crossing or how the minimum horizontal/vertical separation standards are not
met (e.g., the sewer line is 6 inches above or under the water line; for 500 feet on Hayes St reet ,
the edge of sewer pipe is only 6 feet from the edge of water pipe, etc.)
1) For 30 feet on Antler Way, the edge of the vertically relocated sanitary sewer pipe is 3’-4”to
6’ from the edge of an existing water pipe.
2) For 80 feet on Fort Union Blvd, the edge of the new 36 -inch waterline is approximately 5’-
5” feet from the edge of an existing sanitary sewer pipe.
☐ 6. Minimum horizontal and vertical clearances between the sewer and the water lines, from edge of
the pipe to edge of the pipe [If the exact clearance is unknown but it is suspected that the design will
not meet the minimum separation requirement, and if the water system wishes to obtain an exception in
advance, DDW can consider granting an exception with a condition requiring that additional detailed
info rmation be submitted later based on field verification .]
DDW-Eng-0015 Page 1 of 1 6/5/2020
1) Minimum horizontal clearance between the (horizontally relocated) sanitary sewer and
existing water line is approximately 3’-4”.
2) Minimum horizontal clearance between the existing sanitary sewer and new proposed water
line is approximately 5’-5”.
☐ 7. If available, a drawing or schematic of the water line and sewer line layout, showing minimum
clearance, depth, etc.
1) See attached drawing, SLAR -P-14 (plan and profile drawing) and SLAR -U-06 (utility
relocation drawing) found in “Exemption Request Drawings”.
2) See attached drawing, CC -1-P-22, found in “Exemption Request Drawings”.
☐ 8. Sewer line information — new or existing, pipe material, thickness or pressure class, diameter,
joint type, pipe condition (e.g., new, old, recently videoed, etc.), pressurized or gravity feed, etc.
1) Existing gravity sanitary sewer
a. Diameter: 8-inch
b. Pipe material: PVC
c. Pipe condition: Good condition
d. Age: 1973
e. Owner: Cottonwood Improvement District
2) Existing gravity sanitary sewer
a. Diameter: 15-inch
b. Pipe material: PVC SDR35
c. Pipe condition: Good condition
d. Age: 2017
e. Owner: Cottonwood Improvement District
☐ 9. Water line information — new or existing, pipe material, thickness or pressure class, diameter,
joint type, pipe condition (e.g., new, old , deteriorated, etc.), typical water pressure range, etc.
1) Existing water line
a. D rawing: SLAR-P-14 and SLAR-U-06
b. Diameter: 20-inch
c. Pipe material: Steel cylinder Concrete Pipe
d. Thickness: unknown
e. Pipe condition: Good
f. Age: 1981
g. Joint Type: Welded
h. Typical Pressure Range: Unknown, but likely very low pressure
i. Owner: Salt Lake City Department of Public Utilities
2) New waterline (C ottonwood Connector 1, CC -1)
a. Drawing: CC-1 -P-22
b. Diameter: 36-inch
c. Pipe material: Welded steel pipe
d. Thickness: 0.375-inch
e. Pipe condition: N/A - NEW
f. Age: N/A – NEW
g. Joint Type: Welded
h. Typical Pressure Range: 100 psi
DDW-Eng-0015 Page 1 of 1 6/5/2020
i. Owner: Metropolitan Water District of Salt Lake & Sandy, Salt Lake City
Department of Public Utilities
☐ 10. Ground water table conditions based on recent or nearby construction (e.g., known ground water
table depth, very high or low ground water table, whether expected to encounter ground water
during installation, etc.)
For this pipeline project, a geotechnical report was completed in August of 2023 measured
groundwater depth at numerous locations along the pipelines alignment.
1) 0-ft, unobserved.
2) 0-ft, unobserved.
☐ 11. Proposed means to mitigate the risk (e.g., remove/replace the aged vitrified clay sewer pipe;
replace the aged or cracked existing sewer pipe; use thicker or higher pressure class PVC instead
of the typical thin-wall sewer pipe; install an in-situ lining to the existing sewer pipe for XX feet ;
center the sewer line over the crossing to keep the joints as far as possible from the water line;
add plastic warning tape placed 12 inches above the sewer and/or the water line(s) to minimize
possible damage during future excavations; use HDPE pipe for water line or sewer line to
eliminate the joints [if there is no sagging or lack-of-sufficient slope problems for HDPE sewer pipes];
use restrained joints for water line and/or sewer line near the crossing.)
1) Use of higher pressure PVC , proposed relocation is providing a larger vertical seperation
(sanitary sewer is well below the water line), and propose to pull the joints as far away as
possible from the water line.
2) Use of welded steel pipe with a thickness of 0.375-inch.