chapter 8: water supply & sanitary systems€¦ · 8. water supply & sanitary systems city...

Chapter 8: Water Supply & Sanitary SystemsManage, Treat & Reserve

Comprehensive Plan 2040

8. WATER SUPPLY & SANITARY SYSTEMCity of Lauderdale Comprehensive Plan 2040

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8. WATER SUPPLY & SANITARY SYSTEMS City of Lauderdale Comprehensive Plan 2040

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2040 Water Supply & Sanitary

Highlights – What’s to Come

» The St. Paul Regional Water Service supplies the City with clean water.

» Sanitary Sewer services in the City are part of the regional system. Capacity is adequate for existing and forecasted projections through 2040.

INTRODUCTION

This chapter of the City of Lauderdale’s 2040 Comprehensive Plan addresses water supply and wastewater (sanitary sewer) systems in the City. It is consistent with the Metropolitan Council’s Thrive MSP 2040 planning and 2040 Water Resources Policy Plan. This Plan chapter is primarily intended to assist the Metropolitan Council Environmental Services (MCES) with continued operation of the Metropolitan Disposal System (MDS) for wastewater collection and treatment.


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WATER SUPPLY PLAN

Since the late 1990s, St. Paul Regional Water Service (SPRWS) has owned and maintained the water supply utilities in the City of Lauderdale. As the City does not manage its own water supply, a local water supply plan is not required as part of the 2040 Comprehensive Plan. More information about the local water supply plan for the St. Paul Regional Water Service can be found online at www.stpaul.gov/departments/saint-paul-regional-water-services.

Water Sources and Conservation

This source water comes from the Mississippi River and the surrounding watershed. SPRWS also maintains a series of groundwater wells pumping from the Prairie du Chien-Jordan aquifer as a backup supply system. intake station in Fridley, which is located roughly 25 miles northwest of the utility’s water treatment plant

There are currently no private water supplies within the City, and protection of water supply sources for Lauderdale falls outside of local jurisdictional limits. Likely the best way residents and businesses within Lauderdale can contribute to conservation and protection of the local water supply is by encouraging local groundwater recharge. Adding opportunities for water runoff to infiltrate on or near local properties will reduce pollution and contamination and contribute to a more sustainable water supply for the region.

Additionally, residents and businesses can work to conserve the water supply used by reducing water use. Implementing ideas like rain barrels, reduced lawn, and grey-water reuse all contribute to using less water from the municipal water supply. The City will continue to encourage water conservation by promoting education and conservation programs for residents.

Special Well and Boring Construction Area

The City of Lauderdale is within the MDH-designated Twin Cities Army Ammunition Plant (TCAAP) Special Well and Boring Construction Area (SWBCA) which went into effect July 1, 1996 and was most recently updated in April 2016. Groundwater in portions of the designated area has been contaminated with volatile organic compounds (VOCs) from solvents used and disposed at TCAAP in Arden Hills. The designation requires that construction, repair, and sealing of regulated wells and borings within the SWBCA only take place in accordance with the conditions and requirements set forth by the MDH.

Efforts to contain and clean up the contamination at the TCAAP facility and to the south ofTCAAP have been underway for many years through contaminated groundwater treatment


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and removal of water-supply wells known to be contaminated. Additional concern centers around construction of new wells or borings—or modification of existing wells or borings—within the SWBCA that may interfere with cleanup efforts and/or cause further spread of the contamination. It is therefore important for the City of Lauderdale to implement and enforce the requirements of the SWBCA with respect to existing and proposed water supply wells in the area. Of particular significance to Lauderdale, any construction-related and environmental borings are required to follow these regulations.

System Maintenance

Many of the City’s water lines were replaced during road reconstruction projects in the early 2000s. There are currently no plans by SPRWS to replace water mains in Lauderdale. However, the City is currently discussing the possibility of taking back a portion of Eustis Street, and if that were to occur, SPRWS will update the watermains in coordination with proposed road reconstruction project.

WASTEWATER (SANITARY) SEWER SYSTEM

System Capacity Description

Lauderdale’s sewers were originally constructed in the 1950s, and the City completed a group of major reconstruction projects in 2003 to replace and update the streets, sewers, and waterlines. Since the adoption of the 2030 Plan in 2010 the City has been using cured in place pipe (CIPP) to rehabilitate and repair the existing sewer lines that were not updated during the 2000-2003 major street reconstruction projects.

The City of Lauderdale is served by regional sanitary sewer service. Lauderdale’s sanitary sewer system is shown on Map 8-1. The system is divided into five sanitary sewer district defined by points of discharge to sewer trunk lines. Districts 1 and 2 flow to MCES Meter M103, located near 33rd Avenue Southeast and Talmadge Avenue in Minneapolis. Meter M103 and Lauderdale Districts 3 and 4 all flow to MCES Interceptor 1-MN- 301 near 33rd Avenue Southeast and Como Avenue in Minneapolis. District 5 flows to St. Paul’s sewer system at the intersection of Fulham Street and Hoyt Avenue.

Lauderdale does not have a wastewater treatment facility. Wastewater is collected in the City sewer system and discharged to the systems described above; which convey wastewater to the MCES treatment plant at Pig’s Eye Lake in St. Paul. MCES charges Lauderdale for treatment of this wastewater. Districts 3, 4, and 5 are periodically metered by the MCES.


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Map 8-1 Sanitary Sewer System Map

Source: City of Lauderdale

MCES Meter

Inter-community Connection


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System Features

Lauderdale’s sanitary sewer system is composed of approximately 6.7 miles of sewer lines and 156 manholes. There are no lift stations in the system. Most of the sanitary sewers in Lauderdale were replaced between 2000 and 2003, and those not replaced have been lined since 2010. The City redirected flows in District 1 to the north and constructed a trunk line parallel to Highway 280 to carry this flow south. These improvements allowed Lauderdale to abandon four aging lift stations.

There are no on-site septic systems or large sewer users (flow exceeding 0.05 MGD) located within the City. Undeveloped parcels in Lauderdale can be adequately served using existing facilities, so there are no system extensions or new MDS connection points planned. Future improvements will focus on maintenance of the existing system.

Projected Population and Wastewater Flows

Table 8-1 lists the population, households and employment as estimated by the City of Lauderdale in Chapter 3 of this Plan, and identifies and wastewater flow projections issued by the Metropolitan Council in the City of Lauderdale’s 2015 System Statement.

Table 8-1 Lauderdale Wastewater Flow Projections2020 2030 2040

Population 2,490 2,704 3,007Households 1,260 1,364 1,519Employment 890 1,025 1,161Average Wastewater Flow (MGD) 0.23 0.24 0.24Allowable Peak Flow (MGD) 0.90 0.94 0.94

Source: Metropolitan Council (Peak Flow Factor = 3.9), City of Lauderdale, SHC

System Flows and Capacity

System flows have been estimated for current (2018) conditions as well as 2040 projected land use conditions. The average wastewater flow from each sanitary sewer district has been estimated by applying unit flow rates to each land use category. These estimates are summarized in Tables 8-2 and 8-3.

The sanitary sewer system must be capable of handling the anticipated peak flows, estimated by applying a peak flow factor to the average flow. The peak flow factor accounts for flow variability and includes an allowance for infiltration and inflow.


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Exis

ting

2018

La

ndus

e To

tal

Park

&

Rec

reat

ion

Roa

dway

R

OW

Rai

lway

R

OW

Ope

n Sp

ace

Util

itySi

ngle

Fa

mily

R

esid

entia

l

Tow

nhom

e/C

ondo

Apa

rtm

ents

Com

mer

cial

Indu

stria

lIn

stitu

tiona

l

Sew

er D

istr

ict

1158.6

6.43

43.23

5.64

1.23

9.98

73.58

0.98

7.22

2.71

239.17

14.29

13.36

7.85

2.27

342.3

5.74

9.09

4.73

17.27

424.95

11.83

3.95

5.86

0.66

12.53

4.03

54.16

0.59

0.8

2.61

0.72

City

Tot

al269.18

6.43

75.68

9.59

11.12

15.84

89.55

12.58

18.25

2.93

19.75

7.46

Uni

ts p

er a

cre

99

15Pe

rson

s pe

r uni

t 2.5

2.5

1.1

Popu

latio

n2510

1926

283

301

Gal

lons

/per

son/

day

8075

75G

allo

ns/a

cre/

day

100

1800

1800

1238

1000

1000

800

MG

D /

acre

0

00

00.0001

0.0018

0.0012

0.0012

0.0010

0.0010

0.0008

MG

D /

City

0

00

00

0.0016

0.1612

0.0151

0.0219

0.0029

0.0198

0.0060

Sew

er D

istr

ict

10.1432

0.0000

0.0000

0.0000

0.0000

0.0002

0.1324

0.0000

0.0012

0.0000

0.0072

0.0022

20.0404

0.0000

0.0000

0.0000

0.0000

0.0000

0.0240

0.0141

0.0000

0.0023

0.0000

0.0000

30.0299

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0085

0.0214

0.0000

0.0000

0.0000

40.0165

0.0000

0.0000

0.0000

0.0000

0.0001

0.0000

0.0000

0.0000

0.0007

0.0125

0.0032

50.0053

0.0000

0.0000

0.0000

0.0000

0.0000

0.0047

0.0000

0.0000

0.0000

0.0000

0.0006

City

Tot

al0.2353

Sew

er D

istr

ict

Avg

Flo

w

(MG

D)

Peak

Fac

tor

Des

ign

Flow

(MD

G)

Trun

k di

a (in

)sl

ope

(ft/ft

)C

apac

tiy

(MG

D)

Cap

acity

/ D

esig

n

10.1432

3.9

0.5585

150.0018

2.0937

2.3413

20.0404

4.0

0.1618

150.0012

1.7095

1.9117

Subt

otal

to M

103

0.1837

3.9

0.7162

30.0299

4.0

0.1196

40.0165

4.0

0.0660

Subt

otal

to 1

-MN

-301

0.0464

3.8

0.1763

181-MN-301

50.0053

4.0

0.0211

City

Tot

al0.2353

3.8

0.8942

Was

tew

ater

Flo

w a

nd S

yste

m C

apac

ity -

Exis

ting

Are

a (A

cres

)

Ave

rage

Flo

w (M

GD

)

Table 8-2. Wastewater System Capacity - Existing


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Plan

ned

2040

Lan

d U

seTo

tal

Park

, R

ecre

atio

n &

Ope

n Sp

ace

Roa

dway

Rai

lway

Low

D

ensi

ty

Res

dien

tial

Med

ium

D

ensi

ty

Res

iden

tial

Hig

h D

ensi

ty

Res

iden

tial

Indu

stria

lB

usin

ess

Park

Mix

ed

Use

Sew

er D

istr

ict

1158.6

9.02

49.09

5.64

76.06

01.69

17.1

02

39.17

0.14

14.29

11.64

7.85

5.25

342.3

7.59

5.74

4.68

12.33

4.03

7.93

424.95

11.83

3.95

9.17

54.16

0.59

3.57

City

Tot

al269.18

16.75

81.54

9.59

91.27

12.53

14.02

26.27

4.03

13.18

Uni

ts p

er a

cre

59

15Pe

rson

s pe

r uni

t 2.5

2.5

1.1

Popu

latio

n3007

2126

283

598

Gal

lons

/per

son/

day

8080

75G

allo

ns/a

cre/

day

1800

1238

1238

1000

1000

1000

MG

D /

acre

0.0000

0.0000

0.0000

0.0000

0.0018

0.0012

0.0012

0.0010

0.0010

0.0010

MG

D /

City

0.0000

0.0000

0.0000

0.0000

0.1643

0.0150

0.0168

0.0263

0.0040

0.0132

Sew

er D

istr

ict

10.1561

0.0000

0.0000

0.0000

0.1369

0.0000

0.0021

0.0171

0.0000

0.0000

20.0359

0.0000

0.0000

0.0000

0.0210

0.0097

0.0000

0.0000

0.0000

0.0053

30.0330

0.0000

0.0000

0.0000

0.0000

0.0058

0.0153

0.0000

0.0040

0.0079

40.0092

0.0000

0.0000

0.0000

0.0000

0.0000

0.0000

0.0092

0.0000

0.0000

50.0064

0.0000

0.0000

0.0000

0.0064

0.0000

0.0000

0.0000

0.0000

0.0000

City

Tot

al0.2406

0.1643

0.0155

0.0174

0.0263

0.0040

0.0132

Sew

er D

istr

ict

Avg

Flo

w

(MG

D)

Peak

Fac

tor

Des

ign

Flow

(M

DG

)

Trun

k di

a (in

)sl

ope

(ft/ft

)C

apac

tiy

(MG

D)

Cap

acity

/ D

esig

n

10.1561

3.9

0.6088

150.0018

2.0937

2.3515

20.0359

4.0

0.1437

150.0012

1.7095

1.9200

Subt

otal

to M

103

0.1920

3.8

0.7297

30.0330

4.0

0.1321

40.0092

4.0

0.0367

Subt

otal

to 1

-MN

-301

0.0422

3.7

0.1561

181-MN-301

50.0064

4.0

0.0257

City

Tot

al0.2406

3.7

0.8903

Was

tew

ater

Flo

w a

nd S

yste

m C

apac

ity -

2040

Are

a (A

cres

)

Ave

rage

Flo

w (M

GD

)

Table 8-3. Wastewater System Capacity - 2040


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Trunk line capacities are also included in Tables 8-2 and 8-3. The existing trunk system has adequate capacity for existing and estimated flows. Table 8-4 applies forecasted wastewater flows by proposed land use for 10-year increments, identifying residential and commercial flows for the system. All total wastewater flows are within the projected averages and well within peak flow capacity.

Table 8-4. Lauderdale Sanitary Sewer Forecasts by Metered Area2020 2030 2040

Est. Units / Jobs

Avg Flow (MGD)

Est. Units / Jobs

Avg Flow (MGD)

Est. Units / Jobs

Avg Flow (MGD)

Hou

seho

lds M103 1,041 0.1671 1,109 0.1682 1,209 0.1693

Unmetered - St. Paul 15 0.0047 15 0.0056 15 0.0064

Unmetered - Mpls 204 0.0264 240 0.0234 295 0.0204

TOTAL 1,260 0.1982 1,364 0.1972 1,519 0.1961

Empl

oym

ent M103 382 0.0117 393 0.0171 447 0.0224

Unmetered - St. Paul 16 0.0006 0 0 0 0Unmetered - Mpls 492 0.0164 632 0.0188 714 0.0211

TOTAL 890 0.0287 1,025 0.0361 1,161 0.0435

Total Wastewater Flow 0.2269 0.2333 0.2396

Source: Metropolitan Council, City of Lauderdale, Stantec, SHC *Land use designation changes between 2020 and 2040 may account or differing acreages and resulting average flows by use type.

Inflow and Infiltration

Inflow and Infiltration (I/I) can come from several sources contributing non-sanitary flow into the sanitary sewer system. Example sources include surface runoff from roofs and manholes drainage from draintile and sump pumps, and leaks from failing sanitary infrastructure. The Metropolitan Council establishes I/I goals in the 2040 Water Resources Policy Plan for all communities discharging wastewater to the Metropolitan Disposal System (MDS). Communities identified to have excessive I/I in their sanitary sewer systems are required to reduce and eliminate the excess. Lauderdale has previously been identified as a community with excess I/I.

Lauderdale’s I/I Reduction Efforts

In January 2007, the City of Lauderdale initiated a multifaceted Inflow and Infiltration


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reduction program. Initially, the City smoke tested the City and identified a significant source of inflow and infiltration at an industrial business. This issue was corrected and the City was exempted from the I/I program until another exceedance occurred. After MCES changed its metering thresholds, the City had exceedances that became the impetus for on-going efforts to address I/I. Some of the easiest fixes included closing sewer pick holes and rehabilitating leaky manholes. The City also worked closely with another industrial business to redirect its stormwater runoff from the building to surface water and storm sewer features eliminating the conveyance of the building’s runoff into the sanitary sewer system. The “replumbing” of their building was completed in 2016 to accomplish this effort. Concurrently to working with the industrial businesses, the City undertook a flow metering study to determine which portions of the City contributed to I/I exceedance. With grant assistance from the Metropolitan Council, the City has also been able to line the sanitary sewer pipes that were not completed as part of a roadway project.

In 2018, the City will be filling in gaps where pipes have not been replaced north of Larpenteur. Once the project is complete, the City will have only one more project remaining to finish the replacement or lining of the entire system. The City also continually looks for sump pumps draining to the sanitary sewer system as part of the City’s building permit and rental housing inspections programs.

Goals for I/I Management

Lauderdale will continue its efforts to eliminate excess I/I with the following goals for system management:

• Replace sewer linings• Repair cracks and joints in public system• Monitor sump pump drainage• Educate property owners about reducing I/I• Implement residential monitoring program for private sewer line maintenance

Lauderdale will also work cooperatively with other agencies and property owners to educate residents and businesses about the importance of reducing I/I and promote ongoing maintenance of infrastructure on private property. It is particularly important to inspect and repair damaged sewer service lines connected to the MDS, and replace older clay pipes that are beyond their useful life.


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Policies and Regulations

Lauderdale regulates against inflow and infiltration to the sanitary system from surface water sources. City Ordinance 8-2-2-9: Discharge of Surface Water Prohibited states “Except as otherwise expressly authorized in this subdivision, no water from any roof, surface, sump pump, footing tile or drains, swimming pool, any other natural precipitation or groundwater, cooling water, or industrial process shall be discharged into the sanitary sewer system. Dwellings and other buildings and structures which require, because of the infiltration of water into basements, crawl spaces and the like, a sump pump discharge system shall have a permanently installed discharge line which shall not at any time discharge water into the sanitary sewer system.” The ordinance also requires disconnection of any “roof, surface, sump pump, footing tile or drains, swimming pool, cooling water or unpolluted industrial process water now connected and/or discharging into the sanitary sewer system shall disconnect or remove the same.” The City will continue to monitor compliance with this ordinance through its permitting processes.

chapter 8: water supply & sanitary systems€¦ · 8. water supply & sanitary systems city...

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