1. October 19, 2006 Oklahoma Water Resources Board City of Tulsa
Justification for Total Phosphorus Criteria to Protect Public & Private Water Supply Beneficial Use and Aesthetics Use of Lake Eucha and Spavinaw Lake
October 19, 2006
Oklahoma Water Resources Board
City of Tulsa

2. Lake Eucha
and
Spavinaw Lake

3. Lake Eucha and Spavinaw Lake

4. Oklahoma Water Quality Standards Beneficial Use Designations (Eucha & Spavinaw)
Warm Water Aquatic Community
Agriculture
Industrial & Municipal Process and Cooling Water
Primary Body Contact
Public & Private Water Supply
Aesthetics
Fish Consumption
Sensitive Water Supply

5. Problem Definition Oklahoma 303(d) List Impaired Waterbodies
Lake Eucha
Spavinaw Lake
USAP Violations
CAUSE: Dissolved Oxygen – Percent Anoxic (FWP)
SOURCE: Excessive phosphorus (Aesthetics)
Most people in U.S. get their water from CWS.
PWS: ~ 161,000 in U.S.
May be public or privately owned.
CWS: 54,000 systems
Non CWS –~ 108,000 systems
Non-transient ( 19,000)
Transient (>89,000)
SDWA does not protect or cover private water supplies (wells that serve one or a few homes)

6. Problem Explanation
Phosphorus enters the lakes and provides nutrient source for algae.
Excessive P promotes excess algae growth and encourages the growth of nitrogen-fixing blue-green algae.
During growth and decay of algae, geosmin and 2- methylisoborneal (MIB) are released imparting a very bad T&O to the drinking water.
Source: surface or groundwater
More water systems have groundwater than surface water (147,000 vs 14,500)
But more people drink from surface water sources (195 million vs 101,400).
Coagulation and floculation: Removes dirt and other particulates
Filtration: removes all particles from water
Disinfection: chlorine, chlorinates and chlorine dioxides most often used in U.S.
Also, ozone and ????(look at other docs).
Algae increases DBP precursors and potentially algal toxins.

7. Spavinaw Lake water is costly to treat due to excess algae
Cost of additional T&O treatment since 1998…..
Over $5.6 million.
Projected additional T&O cost over the next 10 years…..
Source: surface or groundwater
More water systems have groundwater than surface water (147,000 vs 14,500)
But more people drink from surface water sources (195 million vs 101,400).
Coagulation and floculation: Removes dirt and other particulates
Filtration: removes all particles from water
Disinfection: chlorine, chlorinates and chlorine dioxides most often used in U.S.
Also, ozone and ????(look at other docs).
$7 million.

8. Lakes may become “dead”
(as a drinking water supply)
Cost of abandoning lakes Eucha and Spavinaw and using another water supply….
Over $250 million.
Cost of replacing Lake Eucha and Spavinaw Lake and developing a comparable water supply….
Source: surface or groundwater
More water systems have groundwater than surface water (147,000 vs 14,500)
But more people drink from surface water sources (195 million vs 101,400).
Coagulation and floculation: Removes dirt and other particulates
Filtration: removes all particles from water
Disinfection: chlorine, chlorinates and chlorine dioxides most often used in U.S.
Also, ozone and ????(look at other docs).
It truly is priceless.

9. “No public water system should have to provide more drinking water treatment other than that which is necessary to address naturally occurring pollutant concentrations.”
– Tracy Mehan
Assistant Administrator for Water, EPA
“Responding to contamination can be as much as 200 times as costly as prevention.”
– Office of Ground Water & Drinking Water, EPA
15 of these: eg. Alumuniumm, chloride, color, copper, corrosivity, tds, sulfate, pH, odor, manganese, iron….
National Secondary Drinking Water Regulations (NSDWRs or secondary standards) are non-enforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. EPA recommends secondary standards to water systems but does not require systems to comply. However, states may choose to adopt them as enforceable standards.

10. Additional T&O expenses for treating Spavinaw Lake water
Initial Chemical &
GAC Filter Cost, etc.

11. Tulsa reported one of the worst T&O problems in the country…
Tulsa reported one of the worst T&O problems in the country….(AP, 2000)
Oct 05 – Apr 06
Geosmin Level (ppt)
Oct 00 – Jan 01
Nov 01 – Feb 02
Geosmin detected by humans at 5 –10 ppt !

12. OWRB Lake Study Recommended TP levels Pristine Conditions (No Impact)
% Tot-P Load Reduction TP
(mg/l)
Pristine Conditions (No Impact)
Lake Eucha 95
0.0048
Spavinaw Lake 80
0.0060
OWRB Impairment Study Recommendation
70.4
0.0168
44.6
0.0141

13. Lakes Eucha & Spavinaw are inextricably linked
70.4% P reduction in Lake Eucha requires a TP level of mg/l to get…
…a 44.6% P reduction in Spavinaw Lake and associated mg/l TP level

14. Lake Eucha Spavinaw Lake
0.0168
Mean annual TP concentrations for Lake Eucha open water sites (EUC-01, -02, -16) surface (0.5m) samples, 1998 – 2006.
Spavinaw Lake
0.0141
Mean annual TP concentrations for Spavinaw Lake open water sites (SPA-01, -02, -05) Surface (0.5m) samples, 1998 – 2006.

15. Proposed TP Criteria 785:45-5-10. Public and private water supplies
(8) Phosphorus numerical criterion applicable to certain waters. The long term average total phosphorus concentration at a depth of 0.5 meters below the surface shall not exceed milligrams per liter in Lake Eucha and milligrams per liter in Spavinaw Lake.

16. Tulsa has taken extraordinary measures to control excess P in the watershed.
Over $ 327,330 for BMP research in the watershed.
Over $1.2 million committed toward actual BMPs in the watershed.
Over $1.1 million spent on lake & stream studies, mapping, etc….

17. Questions ?