Water Reuse: Orlando’s Experiences &

Perspectives

Rick Howard, PE

Public Works Director

Water Reuse

The process of using wastewater that has been thoroughly treated and disinfected to remove harmful organisms and substances, such as bacteria, viruses, and heavy metals; then using it as source water for other beneficial uses.

Why Reuse Water?

• Energy savings

• Improved agricultural production

• Environmental benefits to receiving bodies

• Groundwater recharge

• Sustainable

• Conservation of potable water

• CFWI predicted a 250 mgd deficit by the year 2035

Water Reuse History

• LA County California 1929, crop irrigation • San Francisco 1932, landscape irrigation • Tallahassee 1966, crop irrigation • St. Petersburg 1977, dual water distribution, irrigation • Gainesville 1977, groundwater recharge • Orlando 1986, Conserv II, crop irrigation, recharge • Orlando 1987, wetlands hydration

Water Reuse: Orlando’s Beginning

• In 1979, a citizens group filed a law suit against the City of Orlando and Orange County demanding that wastewater discharges to Shingle Creek be halted.

• The City and County were required to cease discharge by March 1988.

Water Reuse: Orlando’s Beginning:

The City and County formed a partnership to develop a joint solution

• Capital facilities owned equally, 50% each

• O&M costs shared based on volume of reclaimed water delivered

• Many alternatives were analyzed for feasibility and economic viability

The Selected Alternative-Water Conserv II

Largest project of its kind in the world

• Citrus Irrigation

• Rapid Infiltration for Back-up

Conserv II WRF: • 21 mgd permitted

• 13.3 mgd actual flow

• In service since 1972, expanded in 1985

• Major upgrades 2009 to 2013

• Future rerating to 25 MGD

Effluent Discharge: • 25% local reuse ( 6,412 residences, 3

golf courses, 57 parks and 4 schools)

• 75% sent to the Distribution Center for agricultural irrigation and groundwater recharge.

Rapid Infiltration 54%

Public Access 27%

Agricultural 19%

Conserv II DC Facility Overview

2 Water Reclamation Facilities

• City of Orlando’s Conserv II WRF

• Orange County’s South Regional WRF

21-Mile 42”/54” Transmission Pipeline

Distribution Center

• Operations and Maintenance Facilities

• 100 MGD Pump Station

• 20 MG Storage Capacity

49-Mile Distribution Network (54” to 6”)

8 RIB Sites on 3,725 Acres

• 72 RIBs (150 Individual Cells)

• 25 miles of RIB Distribution Network

Rapid Infiltration Basins are Vital to Conserv II Distribution Center

RIBs recharge the Floridan Aquifer with:

• Excess wet weather flows

• Daily flows that are not needed for irrigation

Conserv I WRF • 7.5 mgd permitted

• 3.6 mgd actual flow

• In service since 1987

• Located in fastest growing part of the City

Effluent Discharge • 97% local reuse (4,047 residences,

2 golf courses, 64 parks, 7 schools and 1 cooling tower through the ERRWDS

• 3% rapid infiltration basins for groundwater recharge

Eastern Regional RW Distribution System

• Regional project with several partners developed over 12 years

Orange County Utilities

Orlando Utilities Commission

SJRWMD

• 35 miles of 20” to 48” pipeline

• 20 mgd capacity

• Key water supply initiative for East Orlando and East Orange County

Iron Bridge Regional WRF • 40 mgd design

• 22.5 mgd actual flow

• 10.7 mgd Orlando flow

• In service since 1982, expansion in 1988

• Major upgrade in 2008/09

• Receives WW from Orange Co., Seminole Co., Winter Park, Casselberry, and Maitland

Effluent Discharge • 24% Little Econ

• 67% wetlands

• 9% local reuse / ERRWDS

Why Wetlands?

The City desired to expand the Iron Bridge WRF

• Iron Bridge had a limited waste load allocation to the river

• The concentrations of pollutants would have to be lower at higher flows

• Wetlands treatment was selected because of its storage capacity and its efficiency in nutrient removal resulting in the largest created system of its kind at inception

• 35 mgd capacity with 20 to 40 days resident times resulting in a 54% and 19% reduction in N and P respectively

• Now a public park with bike and hiking trails

• World famous birding venue

Iron Bridge

A 17-mile pipeline carries water to the Orlando Wetlands Park

UCF

Bithlo

Chuluota

Oviedo

Waterford

Lakes

City of Orlando-Summary of Reclaimed Water Quality by WRF - 2016

Iron Bridge

Permit Value

(mg/L)

Iron Bridge

Actual Value

(mg/L)*

Con II Permit Value

(mg/L)

Con II Actual Value

(mg/L)*

Con I

Permit Value (mg/L)

Con I

Actual Value

(mg/L)*

CBOD5 4.28 0.81 20.0 1.8 20.0 1.0

TSS 5.0 0.57 5.0 1.0 5.0 1.0

TN 3.08 1.95 10.0 8.9 ** 7.4

TP 0.94 0.29 ** 2.3 ** 5.1

* Annual average values ending Dec. 2016 ** No permit requirement

City of Orlando-Distribution of Reclaimed Water in 2016

Rapid Infiltration 20% of Total

Public Access Reuse 38% of Total

Wetlands Reuse 26% of Total

Surface Discharge 9% of Total

Over 91% of the City’s reclaimed is reused for irrigation, groundwater recharge or wetlands creation.

Agricultural Irrigation 7% of Total

30 Years Later Reclaimed Water is a Valuable Water Resource

1985 2017

Considered a liability Considered a resource

Incentivize customers to take it Customers willing to pay

Unlimited use Conserve use

Not included in water supply plans Integral to water supply plans

Expensive to implement compared to traditional effluent management

Cost effective compared to developing new supplies of water

Challenges Ahead

• Long term storage facilities needed during periods of reduced demands

• Supplemental supplies are needed for high demand periods

• Regional approaches will be more cost effective requiring more partners and possible compromises

• Further environmental needs and the continued requirement for groundwater recharge

• Potential for future regulatory treatment efficiency upgrades

• Conservation and user rates will increase in the future

• Treatment plant rerating and capacity expansion