The City's monitoring system is currently collecting a variety of data valuable for management of its water supply sources and reclaimed water. After reviewing the available date, the following recommendations are offered:

1. Water levels in Silberhorn monitoring well "Well 1" and Port Williams production wells PW-1 and PW-2 are currently measured manually on a twice-weekly basis. This measurement frequency could be reasonably reduced to weekly. Notes should be made as to whether other wells in the wellfield are pumping at the time of measurement.
2. As long as the datalogger at Port Williams is operational, the majority of manual measurements in PW-1 and PW-2 should be static (non-pumping) water levels, although occasional pumping water levels are warranted. During pumping, the thickness of the water column maintained above the pump can be ascertained by the readout in the control room.
3. At the Port Williams wellfield, monitoring wells MW-1 and MW-3 are currently only monitored by the datalogger. Manual measurements should be obtained from these wells on a monthly basis in case of datalogger failure and/or to calibrate the pressure transducers in the wells. Measurements during non-pumping periods are preferable.
4. At the Silberhorn Wellfield, production wells "Well 2" and "Well 3" are currently measured on a monthly basis. Since Well 1 is used as a monitoring well, the main purpose of measuring water levels in Wells 2 and 3 is to ensure that pumping drawdowns do not approach the top of the pump. Monthly water level measurements in Wells 2 and 3 are sufficient, and should be taken when the wells are pumping. Continued weekly measurements at Well 1 should emphasize static conditions, when possible.
5. The City's current monitoring network has diminished slightly due to private well owners denying access to their wells. Monitoring wells are unavailable in the Lower Aquifer and relatively sparse in the Middle Aquifer. Groundwater level monitoring regularly performed by Clallam County and/or Ecology also emphasizes the Shallow Aquifer, with few wells in the Middle Aquifer and no wells in the Lower Aquifer. While the USGS has measured water levels in many wells, detailed monitoring is sporadic and also emphasizes the Shallow Aquifer. One private well owner monitors water levels in the undifferentiated deposits that underlie the Lower Aquifer; however, the data were unavailable at the time of this writing. The current practice of data sharing between agencies (and with the public) should continue. In addition, cooperative efforts should be made by all agencies interested in water resource management on the Sequim-Dungeness Peninsula to include more wells in the Middle and Lower Aquifers. Monthly or quarterly static water level monitoring is highly valuable in documenting aquifer responses to pumping and changes in recharge, as well as calibrating models potentially used to make water management decisions. Private residents and water systems with relatively deep wells should be encouraged to provide access for water-level measurement or share data they collect themselves.
6. The Middle and Lower Aquifers are potentially most susceptible to saltwater intrusion in coastal areas. Agencies involved in water resource monitoring on the Sequim-Dungeness Peninsula attempt to incorporate coastal wells in these aquifers into their monitoring networks. Periodic sampling for measurement of electrical conductance or chloride concentration is advisable for such wells.
7. PGG has prepared various spreadsheets for entry of data that are predominantly recorded by the City in hard-copy format. Data forms maintained by City field staff have been recently submitted to the Public Works office for data entry into these spreadsheets. Hand entered data included: monthly pumping volumes, all manual groundwater level measurements, and daily rainfall. This data entry should continue on a regular basis over the long term. The data can be "stored up" on paper and periodically entered in the spreadsheets. Although rainfall data are eventually published by NOAA, the time delay makes the data unusable for management of irrigation applications on the Demonstration Site. The rainfall spreadsheet should be updated on a twice-monthly basis.
8. The City's sampling program on Bell Creek currently includes two components: 1) laboratory analysis of samples obtained upstream and downstream of the Demonstration Site on an approximately monthly basis, and 2) field analysis of temperature, dissolved oxygen and pH performed several times a month at the Demonstration Site¹⁴. In addition, detailed coliform analysis was performed at up to 6 sites during the summer of 2001. All of these sampling programs use different station ID's, even though sampling locations are sometimes shared between programs. Based on recent recommendations provided to the City's lab, the station nomenclature for the City's Bell Creek sampling should be unified.
9. PGG has provided the City with a spreadsheet for more efficient record keeping for the field analyses discussed above, however, this is not an ideal solution compared to using a database. If significant quantities of data will continue to be generated from Bell Creek monitoring, the City should consider switching their data storage from spreadsheets to a true database, such as Microsoft Access. Associated advantages include: 1) storage of all data in a single file, 2) easy export to other applications, and 3) easy generation of standard reports and graphs. PGG has created a customized database for water quality data that we used in many projects and could assist the City with setting the desired data entry forms and reports in short order.
10. The challenge of detecting potential water quality changes due to the streamflow augmentation requires that some changes be made to the monitoring program: a. Water-quality sampling parameters from Bell Creek can be reduced to the following subset: temperature, DO, specific conductivity, pH, turbidity, TDS, BOD, coliform (total and fecal), nitrate, ammonia, total Kjeldahl nitrogen, total phosphorous, and orthophosphates. Measurement of nitrite, total suspended solids, and alkalinity can be eliminated from Bell Creek samples. Measurement of chloride should be added to the list of parameters.

    b. Bell Creek discharge is currently unmeasured, but is relatively indicated by stage measurements taken at culverts upstream and downstream of Carrie Blake Park. Because the stream is split into two culverts at road crossings near the park entrance and exit, measurement of stream stage at a single (and stable) point in the natural channel is preferred. If desired, stream stage can be related to flow by performing 3 or 4 wading discharge measurements per year. Alternatively, it might be possible to install a weir at one of the pond overflows to obtain accurate discharge measurements.

    c. Correction of the method of analysis for ammonia is already underway. Further calibration of the Hach spectrophotometer used for measuring nitrate and phosphorus should be performed to develop a better understanding of the instrument accuracy. Calibration can be performed by maintaining standards and/or sending duplicate methods to a certified laboratory.

    d. The upstream and downstream stations should always be monitored on the same day and as close to the same time as possible.

    e. In order to better understand potential changes in water quality associated with the ponds on Carrie Blake Park, short-term sampling over several events is recommended. Whereas the stream is already sampled below the lower pond, additional sampling immediately upstream of this pond (for the same water quality parameters) is advised. Similar analysis on the upper pond is not recommended, as it may be obscured by inflow of the reclaimed water.

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¹⁴Stream stages in culverts are also measured during these site visits.  Return