Guidance Manua pdf

 

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1. 

Relay the most recent monitoring data to everyone within the WSD who needs this 

information, 

2. 

Provide recommendations on management practices that need to be used, 

3. 

Provide a forum for relaying technical commentary, and 

4. 

Provide a mechanism for generating feedback from water treatment personnel (lab 

chemists, plant operators, etc.). 

 

During the summer and early fall when MIB/geosmin concentrations begin to increase, 

the  Newsletter should be written and distributed every week, because T&O conditions 

change rapidly. Furthermore, the management strategy must continuously evolve as 

COP gains experience, builds new infrastructure, and employs new technologies. A 

common sequence during a typical week would be: samples collected (day 1); samples 

analyzed (day 2); data and interpretation (day 3), the Newsletter is written and delivered 

by e-mail (day 4) (Figure 3-1). 

 

Another important component is regular  T&O workshops which should be held once or 

twice a year.  The goal of these workshops is to present results of the continuing 

program evaluation, discuss problems, share ideas for improved solutions, and discuss 

future plans.  For example, a spring workshop could be used to prepare for the 

upcoming T&O season.  By this time, the annual hydrologic and water supply situation 

is known, an evaluation of the program successes and failures for the previous season 

should be ready, and the budgetary situation should be well-understood.  A fall-winter 

workshop  would provide an opportunity to evaluate the success of the T&O 

management program during the previous season. 

 

These workshops should include treatment plant operators and chemists, the 

monitoring group, the water resources manager, and managers from the  SRP and 

CAWCD. 

 

 

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SECTION 4 

MONITORING AND PREDICTION 

4.1  MONITORING PROGRAM 

4.1.1  Location of Sampling Sites  

 

The location and timing of T&O problems changes constantly.  It is therefore necessary 

to maintain an extensive monitoring program to allow effective responses to be 

implemented throughout the season, as the situation demands.  A monitoring program 

also provides data to evaluate the T&O program. 

 

A regional monitoring program should include the terminal water supply reservoirs, the 

CAP and SRP water delivery canals, the inlet and outlet of each water treatment plant, 

and the water distribution system.   

 

This section identifies specific locations within the watershed and canal systems that 

would provide significant benefit to the metropolitan Phoenix region, and specific WTPs.  

General criteria for monitoring within pressurized water distribution systems of a 

particular city are also provided.  Proposed sampling sites, based on the three-year T&O 

study, are indicated on Table 4.1. 

 

Table 4-1.  Location and rationale for proposed monitoring sites.   

 

Monitoring Site  

Rationale 

Terminal Lakes 

Lake Havasu (CAP samples) 

Lake Pleasant (SRP samples) 

Lake Bartlett (SRP samples) 

Lake Saguaro (SRP samples) 

Algae growth in the lakes is a primary source of T&O entering 

WTPs; monitoring reservoirs also predicts of the duration of 

T&O occurrence, allowing utilities to order PAC supplies, etc. 

Both the epiliminion and hypolimnion should be sampled during 

summer stratification. 

Rivers 

Verde River at Beeline Hwy 

Salt River at Bluepoint Bridge 

These sites are downstream of terminal lakes and represent 

influent water to the SRP canal system; storm runoff affects 

T&O in rivers. 

CAP Canal 

Above Aqua Fria Siphon 

Wadell Canal 

Above SRP cross-connect 

CAP canal provides water to Union Hills WTP and to the head of 

the SRP canals. Historically T&O levels are lower in CAP water 

than SRP water and offer opportunities to blend sources to 

control T&O. 

Arizona Canal 

Above/below CAP cross-connect 

At Beeline Highway  

Pima Road 

56

th

 Street 

Central Avenue 

For the past 3 years, three different “hot spots” for T&O 

production have been identified. Frequent monitoring has 

identified “hot spots” and allowed for copper treatment or canal 

brushing by SRP to reduce in-canal T&O production. 

South Canal 

Below CAP cross-connect 

End of South Canal 

Quantifies potential production in the South canal and provides 

baseline for Cities of Chandler (Consolidated Canal) and Tempe 

(Tempe Canal) 

Water Treatment Plants  

(Influent and effluent samples) 

Union Hills (CAP canal) 

Squaw Peak (AZ canal@ 24

th

 St) 

Deer Valley (AZ canal@ 24

th

 Ave) 

Val Vista (South Canal) 

Additional City WTPs  

Influent T&O concentrations allow optimization of treatment 

conditions (e.g., PAC type and doses); finished water is quality 

perceived by customers.  PAC treatment efficiency can be 

computed from influent and effluent samples. Determine 

whether in-plant production of MIB/geosmin occurs. 

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