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Site Visit Report

Haynes Generating Station (HnGS)

6801 Westminster Avenue

Long Beach, CA 90803

September 2, 2009 (revised August 16, 2013)

1.0 Background and Objectives

The Environmental Protection Agency (EPA) is in the process of developing 

316(b) cooling water intake structure requirements that reflect the best technology

available (BTA) for minimizing adverse environmental impact for all existing 

power plants and manufacturing facilities. As part of this process, EPA staff is 

visiting electric generators and manufacturers to better understand the cooling 

water intake structure (CWIS) technologies in use at facilities, including the sitespecific characteristics of each facility and how these affect the selection and 

performance of CWIS technologies. EPA is also visiting facilities to better 

understand cooling water use and specific issues or technologies that can affect 

316(b) compliance. EPA selected Haynes Generating Station (HnGS) for a site 

visit due to its coastal location near the Pacific Ocean and its recent repowering 

project. 

2.0 Facility Description

HnGS is a natural gas–fired steam electric generating facility located in the City

of Long Beach in Los Angeles County (a small portion of the facility property lies 

within the City of Seal Beach, Orange County). HnGS is owned and operated by 

the City of Los Angeles Department of Water and Power (LADWP). The facility

occupies approximately 160 acres of an industrially zoned site approximately 2 

miles northeast of the entrance to Alamitos Bay. The property parallels the east 

bank of the San Gabriel River for approximately 3⁄4 mile north of 2

nd Street to 

State Highway 22. The eastern edge of the property is bounded by the Orange 

County Flood Control District Channel.

AES’s Alamitos Generating Station lies opposite HnGS on the west bank of the 

San Gabriel River. A large residential neighborhood, Leisure World, lies across 

the flood control channel and extends the entire length of Haynes’ eastern 

boundary. Another residential neighborhood, Island Village, lies southeast of the 

facility’s southern boundary.

Elevation at the site is relatively flat, with most of the site situated between 10 and 

15 feet above sea level (asl).

The southern portion of the property is occupied by the generating units, parking 

areas, switchyard, and active fuel storage tanks, as well as miscellaneous storage 

and maintenance buildings. Large fuel storage tanks used to occupy the northern 

portion of the property, although they have since been decommissioned and 

removed. This area has been set aside by LADWP for the next planned 
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repowering phase due to commence construction in January 2011, consisting of 

six 100 MW simple cycle combustion turbines with dry cooling.

Wastewater discharges to the San Gabriel River and water withdrawals from 

Alamitos Bay are covered under NPDES Permit No. CA0000353, which is 

administered at the state level by a regional water board. Order No. 00-081, 

issued by the Los Angeles Regional Water Board, expired on May 10, 2005 but 

has been administratively continued to the present. The facility had been 

previously notified that a reissued permit was delayed pending the outcome of the 

State Water Board’s ongoing once-through cooling policy development. At the 

time of EPA’s site visit, it was unclear when the NPDES permit would be 

reissued.

Power generation began in 1962-3 with the commissioning of Units 1 & 2. Units 

5 & 6 were commissioned in 1966-7. Units 3 & 4 have been decommissioned and 

retired and were replaced by combined cycle generating units (Units 8, 9 and 10)

in 2005.

Haynes currently has 165 employees.

3.0 Electricity Generation and Transmission

HnGS currently operates four conventional steam turbine units (Units 1 & 2, 5 & 

6) as well as one combined cycle system that consists of two combustion turbines 

(Units 9 and 10) and a heat recovery steam generator (HRSG)(Unit 8). The 

combined generating capacity for HnGS is approximately 1,625 MW (Table 1).

Facility representatives noted that, with the exception of Units 8, 9 and 10, the 

capacity utilization rate (CUR) at HnGS has consistently trended downward over 

recent years as more modern and efficient sources have come online in the region, 

including an expanded renewable portfolio to meet state greenhouse gas 

objectives. However, depending upon federal and state climate legislation, 

greater dependence on these local plants for base load energy supply and the 

balancing of new intermittent renewable resources may be necessary if LADWP 

is required to undertake an early divestiture of its coal resources.
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Table 1 –HnGS Rated Capacity

Unit Rated capacity

(MW) 2008 CUR

Unit 1 230 13%

Unit 2 230 13%

Unit 5 330 7.3%

Unit 6 26017.3%

Unit 8 575 41%

HnGS total 1625 25%

Energy efficiencies for HnGS’s four natural-gas fired units are typical for units of 

this type and age. Under peak conditions, Units 1 and 2 can operate at 

approximate efficiencies of 33% (9,650 BTU/kWh) while Units 5 & 6 which are 

supercritical units are slightly more efficient at 36% (9,400 BTU/kWh). The 

combined cycle units, taken as a whole, operate more efficiently than 

conventional steam boiler units. Under optimal conditions, the Unit 8, 9 and 10

efficiency can reach 50% or higher (6,800 BTU/kWh). 

LADWP representatives noted that capacity utilization rates are an inexact metric 

for determining a particular facility’s importance to the overall system. Although 

HnGS’s overall CUR is relatively low, it occupies a critical position in LADWP’s 

overall generation and transmission plans during peak periods. The existing 

transmission system is limited in its ability to move electricity between the 

northern and southern sections of LADWP’s service areas during high demand 

periods. The physical location of HnGS, along with LADWP’s other coastal 

units, enables LADWP to maintain a proper balance in the system without 

compromising service. This is particularly notable since LADWP is its own 

balancing authority and as mentioned in Section 10 of this report, as a vertically

integrated utility responsible for its own generation, transmission, and distribution 

of electricity, does not rely on the energy market for power purchases to supply its 

energy needs. Therefore, LADWP believes that its coastal plants serve a critical 

function in providing local resource adequacy, reliability, and system stability.

4.0 Cooling Water System and Intake Structure

All steam units at HnGS, including the Unit 8 HRSG, use ocean water for 

condenser cooling in a single-pass configuration (“once-through cooling”). 

HnGS operates one CWIS to provide condenser cooling water to each of the five 

generating units. Water is withdrawn from San Pedro Bay, via Alamitos Bay 

through seven openings in a bulkhead wall in the northeast corner of the Long 

Beach Marina. Seven 8-foot diameter pipes (only six are typically used) lead 

 

1 Unit 6 was derated from 330 to 260 MW in 2004. The facility ultimately plans to retire both Units 5 and 

6.
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under the San Gabriel River to a manmade canal extending 1.5 miles northeast to 

the station, where six separate screenhouses draw water from the canal.

The screenhouses for Units 1 and 2 are identical, with each containing two screen 

bays fitted with stationary screens. Each screen is 10 feet wide with 3/8-inch wire 

mesh panels. Velocities at the screens are reported to be 0.9 feet per second (fps). 

Downstream of each screen is a circulating water pump rated at 48,000 gallons 

per minute (gpm), for a total capacity of 192,000 gpm, or 276 million gallons per 

day (mgd).

The screenhouses for Units 5 and 6 are identical, with each consisting of four 

screen bays fitted with vertical traveling screens (Figure 1). Each screen is 8 feet 

wide with 3/8-inch wire mesh panels. Velocities at the screens are reported to be 

0.8 feet per second (fps). Screens are normally rotated and cleaned once every 8 

hours. A high-pressure spray removes any debris from the screens, including 

impinged fish, for disposal at a landfill. Two circulating water pumps for each 

unit are located downstream of the screens, with a design rating of 80,000 gpm, 

for a total capacity of 320,000 gpm, or 461 mgd.

Unit 8 uses the two screenhouses previously used by Unit 3 and Unit 4. Each 

screenhouse consists of two screen bays (Figure 2). Each screen is 10 feet wide 

with 3/8-inch wire mesh panels. Velocities at the screens are reported to be 0.7 

feet per second (fps). Screens are normally rotated and cleaned once every 8 

hours. A high-pressure spray removes any debris from the screens, including 

impinged fish, for disposal at a landfill. Two circulating water pumps for each 

unit are located downstream of the screens, with a design rating of 40,000 gpm for 

a total capacity of 160,000 gpm, or 230 mgd. The total design intake flow (DIF) 

for HnGS is 967 mgd.

Figure 1 – Plan View Unit 5 & 6 Screenhouse
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Figure 2 – Unit 8 Screenhouse

Data provided by HnGS representatives shows the average daily intake flows 

from 2005 through 2008 (Table 2).

Table 2 – Average Annual Intake Flows

Year Average Annual Intake Flow (mgd) Percentage of DIF

2005 775 80

2006 772 80

2007 619 64

2008 738 76

A direct correlation between flow and generating capacity utilization cannot be 

easily made since generating CUR do not account for startup/shutdown periods, 

nor do they account for “hot standby” periods during which units are held in a 

near-ready state without generating electricity but still require cooling water 

withdrawals.

HnGS conducts periodic heat treatments to control biofouling (e.g., mussel 

growth) in the cooling water system, although these occur infrequently. During 

heat treatment control gates on the intake and discharge tunnels are closed while a 

bypass gate is opened allowing all water to recirculate through the system until 

the temperature has reached 115° F and has circulated for 120 minutes. 

Biofouling is also controlled through periodic chlorine (sodium hypochlorite) 

injections to the intake flow. Chlorination occurs at each unit for 40 minutes 

twice per day.
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5.0 Impingement and Entrainment Information

Following the adoption of the Phase II rule, HnGS initiated compliance activities 

by submitting a Proposal for Information Collection (PIC) in October 2005 that 

outlined plans to conduct a source water characterization study. Impingement and 

entrainment technologies would also be evaluated for their potential use at the 

site. The PIC identified fine-mesh traveling screens, cylindrical wedgewire 

screens, operational measures, modular inclined screens and restoration as 

technologies that might offer some benefit to HnGS. These evaluations were not 

completed, however, due to the suspension of the Phase II rule. 

At the direction of the Regional Water Board, HnGS conducted a source water 

characterization study in 2006 to determine the composition and abundance of all 

life stages of fish and shellfish that might be influenced by the intake structure

(baseline characterization study). HnGS collected data from nine source water 

sampling locations: six in San Pedro Bay and three in Alamitos Bay. HnGS

collected monthly sampling every six hours in a 24 hour period at each location

which allowed for diel characterization. As part of this study, HnGS also 

conducted impingement and entrainment sampling. HnGS collected impingement 

samples at the traveling screen for each unit four times per week during 20062. 

HGSHNGS conducted biweekly entrainment sampling in front of the bulkhead at 

the Long Beach Marina. Facility representatives stated that 95% of the entrained 

fish were forage fish (gobies and blennies). HnGS published the study in 

November 2007.

Because HnGS does not employ any technologies specifically designed to reduce 

impingement or entrainment, detailed effectiveness studies have not been 

performed on the current cooling system.

6.0 Cooling Tower Feasibility

Facility representatives noted that the feasibility of cooling towers at the HnGS

location has been considered at different points, whether as part of a repowering 

project or to retrofit one of the existing units. HnGS has not conducted a formal 

cost and engineering feasibility analysis, however.

A report prepared for the California Ocean Protection Council (OPC) and State 

Water Board in 2008 identified several obstacles that would influence the 

feasibility of cooling towers at the HnGS location. Sufficient space is available at 

the existing location, primarily in the area where fuel oil tanks have been 

removed. Visual impacts in this location would likely be limited given the 

industrial nature of most of the surrounding area. The proximity of residential 

neighborhoods in Seal Beach, however, would likely require noise mitigation 

measures, such as fan deck barrier walls and grade-level barrier walls.

The 2008 OPC study considered these obstacles and configured three separate 

cooling towers on the northern portion of the facility with appropriate noise 

 

2 The impingement samples do not represent the intake location as the travelling screens are located at the 

end of a long intake canal. 
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abatement technologies. The initial capital cost for these towers was estimated at 

$152 million, excluding long-term costs such as operation and maintenance and 

energy penalty costs.

During the site visit, facility representatives noted that opposition from residents 

in nearby neighborhoods was likely to be significant if cooling towers were 

planned for HnGS, citing the opposition during the Unit 8 repowering project. 

Representatives also noted that since the OPC study was issued, LADWP has 

decided to move forward with a repowering project to replace Units 5 & 6 using 

much of the old tank farm area for the replacement units. This project, consisting 

of six combustion turbines with dry cooling, is slated to commence around 

January 2011. Most significantly, however, representatives noted that retrofitting 

the existing once-through cooling systems for Units 1 & 2, 5 & 6 with cooling 

towers made little economic sense given the age and capacity utilization of each 

unit.

7.0 Debris Handling

Screens at HnGS can collect notable amounts of debris following storm events, 

although floating booms in the intake canal can provide some control. Any debris 

captured on the bar racks or traveling screens is disposed of in a landfill. 

8.0 Repowering/Future Uses

LADWP completed the Unit 3 & 4 repowering project in 2005, replacing these 

units with the Unit 8, 9 and 10 combined cycle system using the existing (oncethrough) cooling system from Units 3 and 4. The new unit consists of two gas 

combustion turbines and the HRSG. The replacement unit generates electricity at 

an efficiency rate 30 to 40 percent higher than Units 3 & 4, reducing per-unit fuel 

consumption, greenhouse gas emissions and NOx emissions.3

LADWP is also pursuing a repowering project for Units 5 & 6 that would retire 

those units and replace them with 6 quick-start gas combustion turbines with a 

total capacity of 600 MW. The gas turbines would be located on land previously

occupied by fuel oil tanks and might complicate placement of any cooling towers 

for other units. Facility representatives noted that this project would likely be air 

cooled.

9.0 Cooling Ponds

HnGS does not use cooling ponds for condenser cooling.

10.0 Ownership

LADWP is the largest municipally owned utility in the country with a service 

population of approximately 4 million people. LADWP maintains a total 

generating capacity of approximately 7,200 MW from diverse portfolio of fossil, 

 

3 According to project engineers, closed-cycle cooling was not considered at the time of the retirement of 

Units 3 and 4.
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hydroelectric, renewable, and nuclear units. HnGS is one of three LADWPowned facilities on the California coast that continues to use once-through cooling 

(together with the Harbor and Scattergood Generating Stations). 

As a vertically integrated utility, LADWP owns and operates the generating, 

transmission and distribution systems that provide electricity to a dedicated 

customer base. This transmission system is not limited to the City of Los 

Angeles, but extends into Nevada, Utah, and Arizona. The system is used to 

import power to all locations (LADWP owned and power exchanges with other 

utilities). This differs from many investor-owned utilities, such as Pacific Gas & 

Electric or Southern California Edison, which must rely on the open market to 

procure a significant portion of their electricity needs. LADWP must obtain 

approval from the Los Angeles City Council to implement any electricity rate 

increases.

LADWP is in the process of developing a new Integrated Resource Plan (IRP)

and is currently soliciting input from the public on this new guidance document. 

This new 2010 IRP will help set the course that LADWP will take in determining 

the best path to take for repowering the existing OTC facilities.

11.0 316(a)

Thermal discharges to surface waters are governed by the state’s Thermal Plan 

(1972), which creates separate requirements for new and existing thermal 

discharges to ocean waters. As an existing thermal discharger, HnGS is subject to 

the Thermal Plan’s narrative requirement that any thermal discharge must ensure 

protection of identified beneficial uses. This requirement is incorporated into the 

existing permit as a temperature limitation of no more than 100° F during normal 

operation and 120°F during heat treatments. The facility does not have a 316(a) 

variance for thermal discharges and has complied with the existing limitation 

during its most recent permit cycle. 

HnGS was notified that the San Gabriel River was being reclassified from an 

ocean to an estuary-type receiving water. Under the Thermal Plan, thermal 

discharges would be limited to no more than 20° F above the background and 

may not exceed 86° F. LADWP has disputed the Regional Board’s interpretation 

and has conducted hydrodynamic studies which affirm LADWP’s claim that the 

San Gabriel River at the point of discharge is characteristic of an enclosed bay

rather than an estuary, which would entail less stringent thermal discharge limits. 

12.0 Ash Handling

HnGS does not generate any ash.

13.0 Air Emissions Controls

Units 1, 2, 5 and 6 each employ selective catalytic reduction to minimize NOx 

emissions. The gas combustion turbines that are part of the Unit 8 combined 
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cycle system employ dry low NOx burners in addition to selective catalytic 

reduction.

14.0 Additional Information

Facility representatives noted that an ongoing legal battle over the availability of 

emission credits within the South Coast Air Quality Management District have 

raised the possibility that no new projects would be able to obtain the necessary

air permits. This would include facilities retrofitted with wet cooling towers.

HnGS’s current NPDES permit, adopted in 2000, does not contain any numeric or 

narrative limitations regarding impingement or entrainment due to cooling water 

withdrawals. The permit carries over findings from previous permits that 

essentially concluded the HnGS cooling water system represented the “best 

technology available” for compliance with 316(b). Although these determinations 

were made prior to the adoption of the state policy on once-through cooling, 

future studies will determine whether this statement is still accurate or whether 

other technologies are available that would represent “best technology available” 

with costs that can be borne by industry. HnGS is required to conduct semiannual impingement monitoring coinciding with scheduled heat treatments. 

In addition to once-through cooling water, HnGS discharges a small volume of 

wastewater from several low volume waste streams. These low volume wastes 

consist of boiler blowdown, floor drains, metal cleaning wastes (chemical and 

non-chemical) and settling basin discharges, and are commingled with oncethrough cooling water prior to discharge through one of 6 permitted outfalls. All 

wastewater is discharged the San Gabriel River and eventually to the Pacific 

Ocean.

Domestic wastewater is captured in portable Baker tanks and disposed of and 

treated offsite. 

HnGS must comply with both water quality-based and technology-based effluent 

limitations for its wastewater discharge to the San Gabriel River. In 1988, the 

State Water Board granted a variance to the total residual chlorine water quality

standard for biofouling control in the cooling system. EPA granted a similar 

variance for the total residual chlorine effluent limitation applicable to steam 

electric facilities. It is not clear if these variances will be revisited in any future 

permit reissuance.

As noted in Section 11.0 above, under the current NPDES permit for HnGS, the 

San Gabriel River at the point of discharge is considered part of the Pacific 

Ocean. Thus, water quality-based limitations are addressed by the state’s Ocean 

Plan. Reclassification of the receiving water from ocean to either an estuary or an 

embayment, will mean that future water quality-based limitations will be derived 

from the California Toxics Rule. Limits under the CTR may be more stringent 

than existing limits for certain parameters (e.g., metals).
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Attachments

Attachment A List of Attendees

Attachment B Site Photos

Attachment C Facility Flows

Attachment D Alden Report for Phase II Compliance (December 2004)

Attachment E Addendum to Alden Report for Phase II Compliance (April 2007)

Attachment F Impingement Mortality and Entrainment Study (November 2007)

Attachment G Impingement Mortality and Entrainment Study Appendices 

(November 2007)

Attachment H Revisions Requested by LADWP
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Attachment A--List of Attendees

Paul Shriner, EPA

Jan Matuszko, EPA

John Kemmerer, EPA Region IX

Tim Havey, Tetra Tech

Kelly Meadows, Tetra Tech

Ken Silver, LADWP

Vic Ybarra, LADWP

Kim Burmahln, LADWP

Susan Damron, LADWP

Dipak Patel, LADWP

Dawson Dong, LADWP

Ian Guthrie, LADWP

Katherine Rubin, LADWP

See also Attachment A (DCN 10-6547A accompanying this document) for the sign-in 

sheet.
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Attachment B—Site Photos
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N
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Attachment C—Facility flows

Please see DCN 10-6547B accompanying this document.

Attachment D--Alden Report for Phase II Compliance (December 2004)

Please see DCN 10-6547C accompanying this document.

Attachment E--Addendum to Alden Report for Phase II Compliance (April 2007)

Please see DCN 10-6547D accompanying this document.

Attachment F--Impingement Mortality and Entrainment Study (November 2007)

Please see DCN 10-6547E accompanying this document.

Attachment G--Impingement Mortality and Entrainment Study Appendices (November 2007)

Please see DCN 10-6547F accompanying this document.
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Attachment H—Revisions Requested by LADWP

In their comment letter on the proposed rule, LADWP requested that EPA make certain revisions to the 

Haynes site visit report in addition to their previous comments. These revisions are below.

1) Replacement for the first paragraph of section 14.0 (Additional Information).

Instead of 

“Facility representatives noted that an ongoing legal battle over the availability of emission credits 

within the South Coast Air Quality Management District have raised the possibility that no new 

projects would be able to obtain the necessary air permits. This would include facilities retrofitted 

with wet cooling towers.”

the text should read

“Permits from the AQMD for repowers of the existing units are viable since emission offsets are 

available on a megawatt for megawatt replacement of existing boilers with new, advanced gas 

turbine units.”